曼昆经济学原理第五版课后答案07
曼昆经济学原理-习题答案
曼昆经济学原理-习题答案第一篇导言第一章经济学十大原理1(列举三个你在生活中面临的重要权衡取合的例子。
答:?大学毕业后(面临着是否继续深造的选择，选择继续上学攻读研究生学位，就意味着在今后三年中放弃参加工作、赚工资和积累社会经验的机会;2、在学习为什么各国之间的贸易不像竞赛一样有赢家和输家呢?答:因为贸易使各国可以专门从事自己最擅长的话动，并从中享有更多的各种各样的物品与劳务。
通过贸易使每个国家可供消费的物质财富增加，经济状况变得更好。
因此，各个贸易国之间既是竞争对手，又是经济合作伙伴。
在公平的贸易中是“双赢”或者“多赢”的结果。
6(市场巾的那只“看不见的手”在做什么呢，答:市场中那只“看不见的手”就是商品价格，价格反映商品自身的价值和社会成本，市场中的企业和家庭在作出买卖决策时都要关注价格。
因此(他们也会不自觉地考虑自己行为的(社会)收益和成本。
从而，这只“看不见的手”指引着干百万个体决策者在大多数情况下使社会福利趋向最大化。
7 解释市场失灵的两个主要原因，并各举出一个例子。
答:市场失灵的主要原因是外部性和市场势力。
外部性是一个人的行为对旁观者棉利的影响。
当一个人小完全承担(或享受)他的行为所造成的成本(或收益)时，就会产生外部性。
举例:如果一个人不承担他在公共场所吸烟的全部成本，他就会毫无顾忌地吸烟。
在这种情况下，政府可以通过制定禁止在公共场所吸烟的规章制度来增加经济福利。
市场势力是指一个人(或一小群人)不适当地影响市场价格的能力。
例如:某种商品的垄断生产者由于几乎不受市场竞争的影响，可以向消费者收取过高的垄断价格。
在这种情况下，规定垄断者收取的价格有可能提高经济效率。
8(为什么生产率是重要的?答:因为一国的生活水平取决于它生产物品与劳务的能力，而对这种能力的最重要的衡量度就是生产率。
生产率越高，一国生产的物品与劳务量就越多。
9什么是通货膨胀，什么引起了通货膨胀?答:通货膨胀是流通中货币量的增加而造成的货币贬值生活中价格总水平上升。
曼昆经济学原理课后答案
曼昆经济学原理课后答案曼昆经济学原理是经济学入门课程中的经典教材，深受广大学生和经济学爱好者的喜爱。
在学习曼昆经济学原理课程时，课后习题是非常重要的一部分，通过做习题可以加深对知识点的理解，检验自己的学习成果。
下面是对曼昆经济学原理课后习题的一些答案解析，希望能够帮助大家更好地掌握课程内容。
1. 为什么经济学家对稀缺性问题感兴趣？经济学家对稀缺性问题感兴趣是因为资源有限而需求无限，这就导致了资源的稀缺性。
经济学家希望通过研究资源的稀缺性问题，找到合理的资源配置方式，以实现资源的最大效益。
2. 什么是机会成本？为什么机会成本是个重要概念？机会成本是指为了得到某种东西而放弃的东西的价值。
它是个重要概念，因为在资源有限的情况下，人们需要在各种选择之间进行权衡，了解机会成本有助于人们做出更明智的决策。
3. 什么是边际分析？为什么它对理解个体决策和市场行为很重要？边际分析是指对增加或减少一单位的行为进行分析，以便了解这种行为对总效用或总成本的影响。
它对理解个体决策和市场行为很重要，因为在现实生活中，人们所面临的决策往往是边际决策，边际分析可以帮助人们更好地理解这些决策。
4. 弹性是什么？弹性的概念对理解需求和供给有何重要性？弹性是指一种变化的程度，可以是价格变化对数量变化的影响，也可以是收入变化对需求变化的影响。
弹性的概念对理解需求和供给有重要性，因为它可以帮助我们预测市场的变化，指导企业和政府的决策。
5. 什么是市场？市场如何协调买者和卖者的行为？市场是指买者和卖者进行交换的地方。
市场通过价格机制来协调买者和卖者的行为，当价格上涨时，供给增加，需求减少，直到市场达到新的均衡；当价格下跌时，供给减少，需求增加，也会达到新的均衡。
6. 什么是生产可能性边界？生产可能性边界如何展示机会成本的概念？生产可能性边界是指在资源和技术固定的情况下，一个国家能够生产的各种商品和服务的组合。
生产可能性边界展示了机会成本的概念，因为它告诉我们，如果一个国家要增加生产某种商品，就必须放弃生产其他商品，这就是机会成本的体现。
曼昆中级宏观经济学课后答案
曼昆中级宏观经济学课后答案【篇一：曼昆宏观经济学-课后答案第6、7版】txt>复习题1、由于整个经济的事件产生于许多家庭与许多企业的相互作用，所以微观经济学和宏观经济学必然是相互关联的。
当我们研究整个经济时，我们必须考虑个别经济行为者的决策。
由于总量只是描述许多个别决策的变量的总和，所以宏观经济理论必然依靠微观经济基础。
2、经济学家是用模型来解释世界，但一个经济学家的模型往往是由符号和方程式构成。
经济学家建立模型有助于解释gdp、通货膨胀和失业这类经济变量。
这些模型之所以有用是因为它们有助于我们略去无关的细节而更加明确地集中于重要的联系上。
模型有两种变量：内生变量和外生变量，一个模型的目的是说明外生变量如何影响内生变量。
3、经济学家通常假设，一种物品或劳务的价格迅速变动使得供给量与需求量平衡，即市场走向供求均衡。
这种假设称为市场出清。
在回答大多数问题时，经济学家用市场出清模型。
持续市场出清的假设并不完全现实。
市场要持续出清，价格就必须对供求变动作出迅速调整。
但是，实际上许多工资和价格调整缓慢。
虽然市场出清模型假设所有工资和价格都是有伸缩性的，但在现实世界中一些工资和价格是粘性的。
明显的价格粘性并不一定使市场出清模型无用。
首先偷格并不总是呆滞的，最终价格要根据供求的变动而调整。
市场出清模型并不能描述每一种情况下的经济，但描述了经济缓慢地趋近了均衡。
价格的伸缩性对研究我们在几十年中所观察到的实际gdp增长这类长期问题是一个好的假设。
第二章宏观经济学数据复习题1、gdp既衡量经济中所有人的收入，又衡量对经济物品与劳务的总支出。
gdp能同时衡量这两件事，是因为这两个量实际上是相同的：对整个经济来说，收入必定等于支出。
这个事实又来自于一个更有基本的事实：由于每一次交易都有一个买者和一个卖者，所以，一个买者支出的每一美元必然成为一个卖者的一美元收入。
2、cpi衡量经济中物价总水平。
它表示相对于某个基年一篮子物品与劳务价格的同样一篮子物品与劳务的现期价格。
曼昆《经济学原理(微观经济学分册)》(第5版)课后习题详解 第1篇 导 言【圣才出品】
第1篇导言第1章经济学十大原理一、概念题1．稀缺性（scarcity）答：经济学研究的问题和经济物品都是以稀缺性为前提的。
稀缺性指在给定的时间内，相对于人的需求而言，经济资源的供给总是不足的，也就是资源的有用性与有限性。
人类消费各种物品的欲望是无限的，满足这种欲望的物品，有的可以不付出任何代价而随意取得，称之为自由物品，如阳光和空气；但绝大多数物品是不能自由取用的，因为世界上的资源（包括物质资源和人力资源）是有限的，这种有限的、为获取它必须付出某种代价的物品，称为“经济物品”。
正因为稀缺性的客观存在，地球上就存在着资源的有限性和人类的欲望与需求的无限性之间的矛盾。
经济学的一个重要研究任务就是：“研究人们如何进行抉择，以便使用稀缺的或有限的生产性资源（土地、劳动、资本品如机器、技术知识）来生产各种商品，并把它们分配给不同的社会成员进行消费。
”也就是从经济学角度来研究使用有限的资源来生产什么、如何生产和为谁生产的问题。
2．经济学（economics）答：经济学是研究如何将稀缺的资源有效地配置给相互竞争的用途，以使人类的欲望得到最大限度满足的科学。
时下经常见诸国内报刊文献的“现代西方经济学”一词，大多也都在这个意义上使用。
自从凯恩斯的名著《就业、利息和货币通论》于1936年发表之后，西方经济学界对经济学的研究便分为两个部分：微观经济学与宏观经济学。
微观经济学是以单个经济主体（作为消费者的单个家庭或个人，作为生产者的单个厂商或企业，以及单个产品或生产要素市场）为研究对象，研究单个经济主体面对既定的资源约束时如何进行选择的科学。
宏观经济学则以整个国民经济为研究对象，主要着眼于对经济总量的研究。
3．效率（efficiency）答：效率指人们在实践活动中的产出与投入之比值，或者是效益与成本之比值，如果比值大，效率就高；反之，比值小，效率就低。
效率与产出或者收益的大小成正比，而与成本或投入成反比，也就是说，如果想提高效率，必须降低成本或投入，提高收益或产出。
曼昆经济学原理 第五版 课后答案 第三篇 供给与需求
第三篇供给与需求(Ⅱ)：市场和福利第七章消费者、生产者与市场效率复习题1．解释买者的支付意愿、消费者剩余和需求曲线如何相关。
答：需求曲线反映了买者的支付意愿。
在任何一种数量时，需求曲线给出的价格表示边际买者的支付意愿。
需求曲线以下和价格以上的总面积是一种物品或劳务市场上所有买者消费者剩余的总和。
2．解释卖者的成本、生产者剩余和供给曲线如何相关。
答：供给曲线的高度与卖者的成本相关。
在任何一种数量时，供给曲线给出的价格表示边际卖者的成本。
价格之下和供给曲线以上的面积衡量市场的生产者剩余。
3．在供求图中，说明市场均衡时的生产者和消费者剩余。
答：APE的面积代表消费者剩余；PBE的面积代表生产者剩余。
图7－1 供求图4．什么是效率?它是经济决策者的惟一目标吗?答：效率是指资源配置使社会所有成员得到的总剩余最大化的性质。
除了效率外，经济决策者还应该关心平等。
实际上，市场交易的好处很像在市场参与者之间分割一块蛋糕，经济决策者不仅要关心如何将经济蛋糕做大，即效率；还要考虑如何在市场参与者之间分这块蛋糕，这就涉及公平问题。
5．看不见的手有什么作用?答：每一个市场参与者都会尽力追求自己的利益，看不见的手指引他们在相互竞争中达到一个并非他们本意想要达到的目的，这就是市场均衡点。
在均衡点上，消费者剩余和生产者剩余总和最大化，整个社会福利达到最大。
6．说出两种市场失灵的名字。
解释为什么每一种都可能使市场结果无效率。
答：市场失灵包括市场势力和外部性。
如果某一市场上存在市场势力，即只有极少部分(可能是一个)买者或卖者可以控制市场价格，他们就会使价格趋向于对他们这一小部分人有益的水平。
于是，市场价格和数量背离供求平衡，社会福利达不到最大，市场失去效率。
外部性是某些市场参与者的行为对旁观者福利的影响。
它使市场福利还要取决于买者评价和卖者成本之外的其他因素。
由于买者和卖者在决定消费和生产时并没有考虑这种负作用。
所以，从整个社会角度来看，市场均衡可能是无效率的。
曼昆经济学原理第五版标准答案宏观
曼昆经济学原理第五版答案宏观【篇一:经济学原理曼昆(宏观部分答案)】>第二十三章一国收入的衡量复习题 1.解释为什么一个经济的收入必定等于其支出? 答：对一个整体经济而言，收入必定等于支出。
因为每一次交易都有两方:买者和卖者。
一个买者的1 美元支出是另一个卖者的1 美元收入。
因此，交易对经济的收入和支出作出了相同的贡献。
由于gｄp 既衡量总收入 13５又衡量总支出,因而无论作为总收入来衡量还是作为总支出来衡量,gdｐ都相等.2 ．生产一辆经济型轿车或生产一辆豪华型轿车,哪一个对gdp的贡献更大？为什么? 答:生产一辆豪华型轿车对gdp的贡献大。
因为gｄｐ是在某一既定时期一个国家内生产的所有最终物品与劳务的市场价值。
由于市场价格衡量人们愿意为各种不同物品支付的量,所以市场价格反映了这些物品的市场价值。
由于一辆豪华型轿车的市场价格高于一辆经济型轿车的市场价格,所以一辆豪华型轿车的市场价值高于一辆经济型轿车的市场价值，因而生产一辆豪华型轿车对gdp 的贡献更大．3 ．农民以２美元的价格把小麦卖给面包师。
面包师用小麦制成面包,以3美元的价格出售。
这些交易对ｇdｐ的贡献是多少呢？答：对ｇdp 的贡献是3美元。
ｇdp 只包括最终物品的价值，因为中间物品的价值已经包括在最终物品的价格中了.４ .许多年以前,peggy 为了收集唱片而花了500 美元。
今天她在旧货销售中把她收集的物品卖了１０0 美元.这种销售如何影响现期gｄp? 答：现期gdｐ只包括现期生产的物品与劳务，不包括涉及过去生产的东西的交易。
因而这种销售不影响现期gdp.5 .列出gdp的四个组成部分。
各举一个例子.答：gdp等于消费(c)+投资(ｉ）+政府购买(g)＋净出口(nｘ) 消费是家庭用于物品与劳务的支出,如汤姆一家人在麦当劳吃午餐.投资是资本设备、存货、新住房和建筑物的购买,如通用汽车公司建立一个汽车厂.政府购买包括地方政府、州政府和联邦政府用于物品与劳务的支出，如海军购买了一艘潜艇．净出口等于外国人购买国内生产的物品(出口)减国内购买的外国物品(进口)。
曼昆《经济学原理(微观经济学分册)》(第5版)课后习题详解-税制的设计(圣才出品)
第12章税制的设计一、概念题1．预算赤字（budget deficit）答：预算赤字指政府的支出大于收入。
政府得到税收收入用T表示，政府用于物品与劳务的支出用G表示。
如果G大于T，这种情况下政府有预算赤字。
一国之所以会出现预算赤字，有许多原因。
有的是为了刺激经济发展而降低税率或增加政府支出，有的则因为政府管理不当，引起大量的逃税或过分浪费。
当一个国家预算赤字累积过高时，就好像一家公司背负的债务过多一样，对国家的长期经济发展而言，并不是一件好事，对于该国货币亦属长期的利空，且日后为了要解决财政赤字只有靠减少政府支出或增加税收，这两项措施对于经济或社会的稳定都有不良的影响。
一国财政赤字若加大，该国货币币值会下跌，反之，若财政赤字缩小，表示该国经济良好，该国货币币值会上扬。
2．预算盈余（budget surplus）答：预算盈余指政府的收入大于支出。
政府得到税收收入用T表示，政府用于物品与劳务的支出用G表示。
如果T大于G，政府的预算盈余就是T G−。
预算盈余是一种预算不平衡的状态，不过它与预算赤字的不平衡是完全不同的两种状态。
盈余表示财政宽松，赤字表示财政困难。
严格地讲，预算应是平衡的，不仅在计划中是平衡的，而且执行中和执行后也应是平衡的。
但在某些时候，适当地安排使财政收入大于财政支出是可以的。
这时，就会出现预算盈余。
3．平均税率（average tax rate）答：平均税率指纳税人实际缴纳的税额与课税对象的比例。
主要用来衡量、控制某地区、某行业的税收负担情况和衡量纳税人的税负水平。
它衡量纳税人收入中用于纳税的比例。
平均税率主要有以下三种：①累进税的平均税率，即按各级税率计算的应纳税额的征税对象数额的比率；②作为平衡总负担水平的控制性税率；③作为编制税收计划和进行税收统计需用的税率。
为了分析重点税源的变化情况，预测变化趋势，找出影响税收收入的因素，在编制税收计划时，需要根据税源统计资料计算出平均税率，即计算出按不同税率计征的税额总和与其相应的计税金额总和之比，并以此作为编制税收计划的依据。
曼昆经济学原理英文版文案加习题答案5章ELASTICITY AND ITS APPLICATION
5ELASTICITY AND ITS APPLICATION WHAT’S NEW IN THE S EVENTH EDITION:There are no major changes to this chapter.LEARNING OBJECTIVES:By the end of this chapter, students should understand:the meaning of the elasticity of demand.what determines the elasticity of demand.the meaning of the elasticity of supply.what determines the elasticity of supply.the concept of elasticity in three very different markets (the market for wheat, the market for oil, and the market for illegal drugs).CONTEXT AND PURPOSE:Chapter 5 is the second chapter of a three-chapter sequence that deals with supply and demand and how markets work. Chapter 4 introduced supply and demand. Chapter 5 shows how much buyersand sellers respond to changes in market conditions. Chapter 6 will address the impact of government polices on competitive markets.The purpose of Chapter 5 is to add precision to the supply-and-demand model. We introduce the concept of elasticity, which measures the responsiveness of buyers and sellers to changes in economic variables such as prices and income. The concept of elasticity allows us to make quantitative observations about the impact of changes in supply and demand on equilibrium prices and quantities.KEY POINTS:The price elasticity of demand measures how much the quantity demanded responds to changes in the price. Demand tends to be more elastic if close substitutes are available, if the good is a luxury rather than a necessity, if the market is narrowly defined, or if buyers have substantial time to react to a price change.The price elasticity of demand is calculated as the percentage change in quantity demanded divided by the percentage change in price. If quantity demanded moves proportionately less than the price, then the elasticity is less than one, and demand is said to be inelastic.If quantity demanded moves proportionately more than the price, then the elasticity is greater than one, and demand is said to be elastic.Total revenue, the total amount paid for a good, equals the price of the good times the quantity sold. For inelastic demand curves, total revenue moves in the same direction as the price. For elastic demand curves, total revenue moves in the opposite direction as the price.The income elasticity of demand measures how much the quantity demanded responds tochanges in consumers’ income. The cross-price elasticity of demand measures how much the quantity demanded of one good responds to the price of another good.The price elasticity of supply measures how much the quantity supplied responds to changes in the price. This elasticity often depends on the time horizon under consideration. In most markets, supply is more elastic in the long run than in the short run.The price elasticity of supply is calculated as the percentage change in quantity supplied divided by the percentage change in price. If quantity supplied moves proportionately less than the price, then the elasticity is less than one, and supply is said to be inelastic.If quantity supplied moves proportionately more than the price, then the elasticity is greater than one, and supply is said to be elastic.The tools of supply and demand can be applied in many different kinds of markets. This chapter uses them to analyze the market for wheat, the market for oil, and the market for illegal drugs.CHAPTER OUTLINE:I. The Elasticity of DemandA. Definition of elasticity: a measure of the responsiveness of quantity demanded orquantity supplied to one of its determinants.B. The Price Elasticity of Demand and Its Determinants1. Definition of price elasticity of demand: a measure of how much the quantitydemanded of a good responds to a change in the price of that good, computed as thepercentage change in quantity demanded divided by the percentage change in price.2. Determinants of the Price Elasticity of Demanda. Availability of Close Substitutes: the more substitutes a good has, the moreelastic its demand.b. Necessities versus Luxuries: necessities are more price inelastic.c. Definition of the market: narrowly defined markets (ice cream) have moreelastic demand than broadly defined markets (food).d. Time Horizon: goods tend to have more elastic demand over longer time horizons.C. Computing the Price Elasticity of Demand1. Formula2. Example: the price of ice cream rises by 10% and quantity demanded falls by 20%.Price elasticity of demand = (20%)/(10%) = 23. Because there is an inverse relationship between price and quantity demanded (theprice of ice cream rose by 10% and the quantity demanded fell by 20%), the price elasticity of demand is sometimes reported as a negative number. We will ignorethe minus sign and concentrate on the absolute value of the elasticity.D. The Midpoint Method: A Better Way to Calculate Percentage Changes and Elasticities1. Because we use percentage changes in calculating the price elasticity of demand,the elasticity calculated by going from one point to another on a demand curvewill be different from an elasticity calculated by going from the second point tothe first. This difference arises because the percentage changes are calculatedusing a different base.a. A way around this problem is to use the midpoint method.b. Using the midpoint method involves calculating the percentage change in eitherprice or quantity demanded by dividing the change in the variable by themidpoint between the initial and final levels rather than by the initial levelitself.c. Example: the price rises from $4 to $6 and quantity demanded falls from 120 to80.% change in price = (6 −4)/5 × 100 = 40%% change in quantity demanded = (120 − 80)/100 x 100 = 40%price elasticity of demand = 40/40 = 1E. The Variety of Demand Curves1. Classification of Elasticitya. When the price elasticity of demand is greater than one, demand is defined tobe elastic.b. When the price elasticity of demand is less than one, the demand is defined tobe inelastic.c. When the price elasticity of demand is equal to one, the demand is said to haveunit elasticity.2. In general, the flatter the demand curve that passes through a given point, themore elastic the demand.3. Extreme Casesa. When the price elasticity of demand is equal to zero, the demand is perfectlyinelastic and is a vertical line.b. When the price elasticity of demand is infinite, the demand is perfectlyelastic and is a horizontal line.4. FYI: A Few Elasticities from the Real WorldF. Total Revenue and the Price Elasticity of Demand1. Definition of total revenue: the amount paid by buyers and received by sellers ofa good, computed as the price of the good times the quantity sold.2. If demand is inelastic, the percentage change in price will be greater than thepercentage change in quantity demanded.a. If price rises, quantity demanded falls, and total revenue will rise (becausethe increase in price will be larger than the decrease in quantity demanded).b. If price falls, quantity demanded rises, and total revenue will fall (becausethe fall in price will be larger than the increase in quantity demanded).3. If demand is elastic, the percentage change in quantity demanded will be greaterthan the percentage change in price.a. If price rises, quantity demanded falls, and total revenue will fall (becausethe increase in price will be smaller than the decrease in quantity demanded).b. If price falls, quantity demanded rises, and total revenue will rise (becausethe fall in price will be smaller than the increase in quantity demanded).4. If demand is unit elastic, the percentage change in price will be equal to thepercentage change in quantity demanded.a. If price rises, quantity demanded falls, and total revenue will remain the same(because the increase in price will be equal to the decrease in quantitydemanded).b. If price falls, quantity demanded rises, and total revenue will remain the same(because the fall in price will be equal to the increase in quantity demanded).G. Elasticity and Total Revenue along a Linear Demand Curve1. The slope of a linear demand curve is constant, but the elasticity is not.a. At points with a low price and a high quantity demanded, demand is inelastic.b. At points with a high price and a low quantity demanded, demand is elastic.2. Total revenue also varies at each point along the demand curve.H. Other Demand Elasticities1. Definition of income elasticity of demand: a measure of how much the quantitydemanded of a good responds to a change in consumers’ income, computed as the percentage change in quantity demanded divided by the percentage change in income.a. FormulaFigure 4Note that when demand is elastic and price falls, total revenue rises. Also point out that once demand is inelastic, any further decrease in price% change in quantity demandedIncome elasticity of demand =% change in incomeb. Normal goods have positive income elasticities, while inferior goods havenegative income elasticities.ALTERNATIVE CLASSROOM EXAMPLE:John’s income rises from $20,000 to $22,000 and the quantity of hamburger he buyseach week falls from 2 pounds to 1 pound.% change in quantity demanded = (1−2)/ x 100 = %% change in income = (22,000 −20,000)/21,000 x 100 = %c. Necessities tend to have small income elasticities, while luxuries tend to havelarge income elasticities.2. Definition of cross-price elasticity of demand: a measure of how much the quantitydemanded of one good responds to a change in the price of another good, computedas the percentage change in the quantity demanded of the first good divided by the percentage change in the price of the second good.a. Formulab. Substitutes have positive cross-price elasticities, while complements havenegative cross-price elasticities.ALTERNATIVE CLASSROOM EXAMPLE:The price of apples rises from $ per pound to $ per pound. As a result, thequantity of oranges demanded rises from 8,000 per week to 9,500.% change in quantity of oranges demanded = (9,500 − 8,000)/8,750 x 100 = %% change in price of apples = − / x 100 = 40%II. The Elasticity of SupplyA. The Price Elasticity of Supply and Its Determinants1. Definition of price elasticity of supply: a measure of how much the quantitysupplied of a good responds to a change in the price of that good, computed as thepercentage change in quantity supplied divided by the percentage change in price.2. Determinants of the Price Elasticity of Supplya. Flexibility of sellers: goods that are somewhat fixed in supply (beachfrontproperty) have inelastic supplies.b. Time horizon: supply is usually more inelastic in the short run than in thelong run.B. Computing the Price Elasticity of Supply1. Formula2. Example: the price of milk increases from $ per gallon to $ per gallon and thequantity supplied rises from 9,000 to 11,000 gallons per month.% change in price = –/ × 100 = 10%% change in quantity supplied = (11,000 –9,000)/10,000 × 100 = 20%Price elasticity of supply = (20%)/(10%) = 2C. The Variety of Supply Curves1. In general, the flatter the supply curve that passes through a given point, themore elastic the supply.2. Extreme Casesa. When the elasticity is equal to zero, the supply is said to be perfectlyinelastic and is a vertical line.b. When the elasticity is infinite, the supply is said to be perfectly elastic andis a horizontal line.3. Because firms often have a maximum capacity for production, the elasticity ofsupply may be very high at low levels of quantity supplied and very low at highlevels of quantity supplied.III. Three Applications of Supply, Demand, and ElasticityA. Can Good News for Farming Be Bad News for Farmers1. A new hybrid of wheat is developed that is more productive than those used in thepast. What happens2. Supply increases, price falls, and quantity demanded rises.3. If demand is inelastic, the fall in price is greater than the increase in quantitydemanded and total revenue falls.4. If demand is elastic, the fall in price is smaller than the rise in quantitydemanded and total revenue rises.5. In practice, the demand for basic foodstuffs (like wheat) is usually inelastic.a. This means less revenue for farmers.b. Because farmers are price takers, they still have the incentive to adopt thenew hybrid so that they can produce and sell more wheat.c. This may help explain why the number of farms has declined so dramatically overthe past two centuries.d. This may also explain why some government policies encourage farmers todecrease the amount of crops planted.B. Why Did OPEC Fail to Keep the Price of Oil HighFigure 8Short Run Long Run1. In the 1970s and 1980s, OPEC reduced the amount of oil it was willing to supply toworld markets. The decrease in supply led to an increase in the price of oil and a decrease in quantity demanded. The increase in price was much larger in the short run than the long run. Why2. The demand and supply of oil are much more inelastic in the short run than thelong run. The demand is more elastic in the long run because consumers can adjust to the higher price of oil by carpooling or buying a vehicle that gets bettermileage. The supply is more elastic in the long run because non-OPEC producerswill respond to the higher price of oil by producing more.C. Does Drug Interdiction Increase or Decrease Drug-Related Crime1. The federal government increases the number of federal agents devoted to the waron drugs. What happensa. The supply of drugs decreases, which raises the price and leads to a reductionin quantity demanded. If demand is inelastic, total expenditure on drugs (equalto total revenue) will increase. If demand is elastic, total expenditure willfall.b. Thus, because the demand for drugs is likely to be inelastic, drug-relatedcrime may rise.2. What happens if the government instead pursued a policy of drug educationa. The demand for drugs decreases, which lowers price and quantity supplied. Totalexpenditure must fall (because both price and quantity fall).b. Thus, drug education should not increase drug-related crime.SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. The price elasticity of demand is a measure of how much the quantity demanded of agood responds to a change in the price of that good, computed as the percentage change in quantity demanded divided by the percentage change in price.When demand is inelastic (a price elasticity less than 1), a price increase raisestotal revenue, and a price decrease reduces total revenue. When demand is elastic (a price elasticity greater than 1), a price increase reduces total revenue, and a price decrease increases total revenue. When demand is unit elastic (a price elasticity equal to 1), a change in price does not affect total revenue.2. The price elasticity of supply is a measure of how much the quantity supplied of agood responds to a change in the price of that good, computed as the percentage change in quantity supplied divided by the percentage change in price.The price elasticity of supply might be different in the long run than in theshort run because over short periods of time, firms cannot easily change the sizes Figure 9(a) Drug Interdiction (b) Drug Educationof their factories to make more or less of a good. Thus, in the short run, thequantity supplied is not very responsive to the price. However, over longerperiods, firms can build new factories, expand existing factories, close oldfactories, or they can enter or exit a market. So, in the long run, the quantitysupplied can respond substantially to a change in price.3. A drought that destroys half of all farm crops could be good for farmers (at leastthose unaffected by the drought) if the demand for the crops is inelastic. Theshift to the left of the supply curve leads to a price increase that will raisetotal revenue if the price elasticity of demand is less than 1.No one farmer would have an incentive to destroy her crops in the absence of adrought because she takes the market price as given. Only if all farmersdestroyed a portion of their crops together, for example through a governmentprogram, would this plan work to make farmers better off.Questions for Review1. The price elasticity of demand measures how much quantity demanded responds to achange in price. The income elasticity of demand measures how much quantitydemanded responds to changes in consumers' income.2. The determinants of the price elasticity of demand include the availability ofclose substitutes, whether the good is a necessity or a luxury, the breadth of thedefinition of the market, and the time horizon. Goods with close substitutes havegreater elasticities, luxury goods have greater price elasticities thannecessities, goods in more narrowly defined markets have greater elasticities, andthe elasticity of demand is greater the longer the time horizon.3. An elasticity greater than one means that demand is elastic. When the elasticityis greater than one, the percentage change in quantity demanded exceeds thepercentage change in price. When the elasticity equals zero, demand is perfectly inelastic. There is no change in quantity demanded when there is a change in price.4. Figure 1 presents a supply-and-demand diagram, showing the equilibrium price, P,the equilibrium quantity, Q, and the total revenue received by producers. Total revenue equals the equilibrium price times the equilibrium quantity, which is the area of the rectangle shown in the figure.Figure 15. If demand is elastic, an increase in price reduces total revenue. With elasticdemand, the quantity demanded falls by a greater percentage than the price rises.As a result, total revenue moves in the opposite direction as the price. Thus, if price rises, total revenue falls.6. A good with income elasticity less than zero is called an inferior good because asincome rises, the quantity demanded declines.7. The price elasticity of supply is calculated as the percentage change in quantitysupplied divided by the percentage change in price. It measures how much quantity supplied responds to changes in price.8. If a fixed quantity of a good is available and no more can be made, the priceelasticity of supply is zero. Regardless of the percentage change in price, therewill be no change in the quantity supplied.9. Destruction of half of the fava bean crop is more likely to hurt fava bean farmersif the demand for fava beans is very elastic. Destruction of half of the cropcauses the supply curve to shift to the left resulting in a higher price of favabeans. When demand is very elastic, an increase in price leads to a decrease intotal revenue because the decrease in quantity demanded outweighs the increase inprice.Quick Check Multiple Choice1. a2. b3. d4. c5. a6. cProblems and Applications1. a. Mystery novels have more elastic demand than required textbooks because mysterynovels have close substitutes and are a luxury good, while required textbooksare a necessity with no close substitutes. If the price of mystery novels wereto rise, readers could substitute other types of novels, or buy fewer novelsaltogether. But if the price of required textbooks were to rise, students wouldhave little choice but to pay the higher price. Thus, the quantity demanded ofrequired textbooks is less responsive to price than the quantity demanded ofmystery novels.b. Beethoven recordings have more elastic demand than classical music recordingsin general. Beethoven recordings are a narrower market than classical musicrecordings, so it is easier to find close substitutes for them. If the price of Beethoven recordings were to rise, people could substitute other classicalrecordings, like Mozart. But if the price of all classical recordings were torise, substitution would be more difficult. (A transition from classical musicto rap is unlikely!) Thus, the quantity demanded of classical recordings isless responsive to price than the quantity demanded of Beethoven recordings.c. Subway rides during the next five years have more elastic demand than subwayrides during the next six months. Goods have a more elastic demand over longertime horizons. If the fare for a subway ride was to rise temporarily, consumers could not switch to other forms of transportation without great expense orgreat inconvenience. But if the fare for a subway ride was to remain high for a long time, people would gradually switch to alternative forms of transportation.As a result, the quantity demanded of subway rides during the next six monthswill be less responsive to changes in the price than the quantity demanded ofsubway rides during the next five years.d. Root beer has more elastic demand than water. Root beer is a luxury with closesubstitutes, while water is a necessity with no close substitutes. If the price of water were to rise, consumers have little choice but to pay the higher price.But if the price of root beer were to rise, consumers could easily switch toother sodas or beverages. So the quantity demanded of root beer is moreresponsive to changes in price than the quantity demanded of water.2. a. For business travelers, the price elasticity of demand when the price oftickets rises from $200 to $250 is [(2,000 – 1,900)/1,950]/[(250 – 200)/225]= = . For vacationers, the price elasticity of demand when the price oftickets rises from $200 to $250 is [(800 – 600)/700] / [(250 – 200)/225] == .b. The price elasticity of demand for vacationers is higher than the elasticityfor business travelers because vacationers can choose a substitute more easilythan business travelers. For example, vacationers can choose a different mode of transportation (like driving or taking the train), a different destination, a different departure date, and a different return date. They may also choose to not travel at all. Business travelers are less likely to do so because their schedules are less adaptable.3. a. The percentage change in price is equal to – / x 100 = 20%. If the priceelasticity of demand is , quantity demanded will fall by 4% in the short run [ ]. If the price elasticity of demand is , quantity demanded will fall by 14% in the long run [].b. Over time, consumers can make adjustments to their homes by purchasingalternative heat sources such as natural gas or electric furnaces. Thus, they can respond more easily to the change in the price of heating oil in the long run than in the short run.4. If quantity demanded fell, price must have increased according to the law ofdemand. For a price increase to increase total revenue, the percentage increase in the price must be greater than the percentage decline in quantity demanded. Therefore, demand is inelastic.5. , a. The effect on the market for coffee beans is shown in Figure 2. When ahurricane destroys half of the crop, the supply of coffee beans decreases, the price of coffee beans increases, and the quantity decreases.QuantityPrice Figure 2Demand S 1 S 2b. The effect on the market for cups of coffee is shown in Figure 2. When theprice of coffee beans, an important input into the production of a cup ofcoffee, increases, the supply of cups of coffee decreases, the price of a cup of coffee increases, and the quantity decreases.Because cups of coffee have an inelastic demand, when the price of a cup ofcoffee increases, the total expenditure on coffee increases.c. The effect on the market for donuts is shown in Figure 3. When the price ofcoffee increases and the quantity demanded of coffee decreases, consumersdemand fewer donuts because coffee and donuts are complements. When demanddecreases, the price of donuts decreases.Because donuts have an inelastic demand, when the price of donuts decreases,the total expenditure on donuts decreases.6. a. If your income is $10,000, your price elasticity of demand as the price of DVDsrises from $8 to $10 is [(40 – 32)/36]/[(10 – 8)/9] = = 1. If your income is $12,000, the elasticity is [(50 – 45)/]/[(10 – 8)/9] = = .b. If the price is $12, your income elasticity of demand as your income increasesfrom $10,000 to $12,000 is [(30 – 24)/27]/[(12,000 – 10,000)/11,000] = = . Price Figure 3If the price is $16, your income elasticity of demand as your income increases from $10,000 to $12,000 is [(12 – 8)/10]/[(12,000 – 10,000)/11,000] = = .7. a. If Maria always spends one-third of her income on clothing, then her incomeelasticity of clothing demand is one, because maintaining her clothingexpenditures as a constant fraction of her income means the percentage changein her quantity of clothing must equal her percentage change in income.b. Maria's price elasticity of clothing demand is also one, because everypercentage point increase in the price of clothing would lead her to reduce her quantity purchased by the same percentage.c. Because Maria spends a smaller proportion of her income on clothing, then forany given price, her quantity demanded will be lower. Thus, her demand curvehas shifted to the left. Because she will again spend a constant fraction ofher income on clothing, her income and price elasticities of demand remain one.8. a. The percentage change in price (using the midpoint formula) is – / × 100%= %. Therefore, the price elasticity of demand is = , which is very elastic.b. Because the demand is inelastic, the Transit Authority's revenue rises when thefare rises.c. The elasticity estimate might be unreliable because it is only the first monthafter the fare increase. As time goes by, people may switch to other means oftransportation in response to the price increase. So the elasticity may belarger in the long run than it is in the short run.9. Walt's price elasticity of demand is zero, because he wants the same quantityregardless of the price. Jessie's price elasticity of demand is one, because he spends the same amount on gas, no matter what the price, which means hispercentage change in quantity is equal to the percentage change in price.10. a. With a price elasticity of demand of , reducing the quantity demanded ofcigarettes by 20% requires a 50% increase in price, because 20/50 = . With the price of cigarettes currently $2, this would require an increase in the priceto $ a pack using the midpoint method (note that ($ – $2)/$ = .50).b. The policy will have a larger effect five years from now than it does one yearfrom now. The elasticity is larger in the long run, because it may take sometime for people to reduce their cigarette usage. The habit of smoking is hardto break in the short run.c. Because teenagers do not have as much income as adults, they are likely to havea higher price elasticity of demand. Also, adults are more likely to beaddicted to cigarettes, making it more difficult to reduce their quantitydemanded in response to a higher price.11. To determine whether you should increase or decrease the price of admissions, youneed to know if the demand is elastic or inelastic. If demand is elastic, adecline in the price of admissions will increase total revenue. If demand isinelastic, an increase in the price of admissions will cause total revenue to rise.12. A worldwide drought could increase the total revenue of farmers if the priceelasticity of demand for grain is inelastic. The drought reduces the supply of grain, but if demand is inelastic, the reduction of supply causes a large increase in price. Total farm revenue would rise as a result. If there is only a drought in Kansas, Kansas’ production is not a large enough proportion of the total farm product to have much impact on the price. As a result, price does not change (or changes by only a slight amount), while the output by Kansas farmers declines, thus reducing their income.。
曼昆经济学原理课后答案
第一篇导言第一章经济学十大原理复习题1．列举三个你在生活中面临的重要权衡取舍的例子。
答：①大学毕业后，面临着是否继续深造的选择，选择继续上学攻读研究生学位，就意味着在今后三年中放弃参加工作、赚工资和积累社会经验的机会；②在学习内容上也面临着很重要的权衡取舍，如果学习《经济学》，就要减少学习英语或其他专业课的时间；③对于不多的生活费的分配同样面临权衡取舍，要多买书，就要减少在吃饭、买衣服等其他方面的开支。
2．看一场电影的机会成本是什么?答：看一场电影的机会成本是在看电影的时间里做其他事情所能获得的最大收益，例如：看书、打零工。
3．水是生活必需的。
一杯水的边际利益是大还是小呢?答：这要看这杯水是在什么样的情况下喝，如果这是一个人五分钟内喝下的第五杯水，那么他的边际利益很小，有可能为负；如果这是一个极度干渴的人喝下的第一杯水，那么他的边际利益将会极大。
4．为什么决策者应该考虑激励?答：因为人们会对激励做出反应。
如果政策改变了激励，它将使人们改变自己的行为，当决策者未能考虑到行为如何由于政策的原因而变化时，他们的政策往往会产生意想不到的效果。
5．为什么各国之间的贸易不像竞赛一样有赢家和输家呢?答：因为贸易使各国可以专门从事自己最擅长的活动，并从中享有更多的各种各样的物品与劳务。
通过贸易使每个国家可供消费的物质财富增加，经济状况变得更好。
因此，各个贸易国之间既是竞争对手，又是经济合作伙伴。
在公平的贸易中是“双赢”或者“多赢”的结果。
6．市场中的那只“看不见的手”在做什么呢?答：市场中那只“看不见的手”就是商品价格，价格反映商品自身的价值和社会成本，市场中的企业和家庭在作出买卖决策时都要关注价格。
因此，他们也会不自觉地考虑自己行为的(社会)收益和成本。
从而，这只“看不见的手”指引着千百万个体决策者在大多数情况下使社会福利趋向最大化。
7．解释市场失灵的两个主要原因，并各举出一个例子。
答：市场失灵的主要原因是外部性和市场势力。
经济学基础(曼昆)课后习题答案
经济学基础（曼昆）课后习题答案第一章经济学十大原理一、为每个关键术语选择一个定义关键术语定义--------------稀缺性1、在社会成员中平等地分配利益的特征--------------经济学2、市场不能有效的配置资源的状况--------------效率3、有限的资源和无限的欲望--------------公平4、一个工人一小时所生产的物品与劳务量--------------理性5、市场上只有一个买者的情况--------------机会成本6、利己的市场参与者可以不知不觉的使整体社会福利最大化的原理--------------边际变动7、社会从其稀缺资源中得到最多东西的特性--------------激励8、社会和企业在市场上的相互交易决定资源配置的经济--------------市场经济9、经济活动的波动--------------产权10、当一个人的行为对旁观者有影响时的情况--------------“看不见的手”11、物价总水平的上升--------------市场失灵12、对现行计划的增量调整--------------外部性13、研究社会如何管理其稀缺资源--------------市场势力14、获得某种东西所退出的东西--------------寡头垄断15、一个人或一群人不适度的影响市场价格的能力--------------生产率16、某种引发人行动的东西--------------通货膨胀17、一个人拥有并使用稀缺资源的能力--------------经济周期18、为了达到目标而尽可能系统性的努力做到最出色二、判断正误--------------1、当政府用税收和福利再分配总收入时，经济显得更有效率。
-------------2、当经济学家说“天下没有免费的午餐”时，他们是指所有经济决策都涉及权衡取舍。
-------------3、亚当斯墨的“看不到的手”的概念叙述了公司经营如何像是一只“看不到的手”晃至消费者的钱包中。