Problem SetⅠ
PartⅠ(True or Fal)
1.There are3goods.The price of good1is-1,the price of good2is+1,and the price of good3is+
2.It is physically possible for a consumer to consume any commodity bundle with nonnegative amounts of each good.A consumer who has an income of10could afford to consume some commodity bundles that include5units of good1and6units of good2.
2.If all prices are doubled and money income is left the same,the budget t does not change becau relative prices do not change.
3.If there are two goods and the prices of both goods ri,then the budget line must become steeper.
4.If someone has the utility function U=1,000+2min{x,y},then x and y are perfect complements for that person.
5.If there are two goods,if a consumer prefers more of each good to less,and if she has a diminishing marginal rate of substitution,then her preferences are convex.
6.If preferences are convex,then for any commodity bundle x,the t of commodity bundles that are wor than x is a convex t.
7.Bill Katz prefers more of good1to less and he prefers less of good2to more. Bill has convex preferences.If we draw his indifference curves with good1on the horizontal axis and good2on the vertical axis,then his indifference curves have positive slope but get steeper as they ri.
8.A consumer who is unable to detect small differences in the amount of water in her beer could have a transitive strict preference relation but is unlikely to have a transitive indifference relation.
9.If Melody has more classical records than rock and roll records,she is willing to exchange exactly1classical record for2rock and roll records,but if she has more rock and roll records than classical records,then she is willing to exchange exactly1 rock and roll record for2classical records.Melody has convex preferences.
10.With quasilinear preferences,the slope of indifference curves is constant along all rays through the origin.
11.Wanda Lott has the utility function U(x,y)=max{x,y}.Wanda’s preferences are convex.思考的英文短语
12.Mr.Surly consumes only two goods and hates them both.His utility function is U(x,y)=-max{x,y}.Mr.Surly has(weakly)convex preferences.
13.Alice’s utility function is U(x,y)=x2y.Steve’s utility function is U(x,y)=x2y+ 2x.Alice and Steve have the same preferences since Steve’s utility function is a monotonic transformation of Alice’s.
14.A consumer has preferences reprented by the utility function U(x1,x2)= 10(x21+2x1x2+x22)-50.For this consumer,goods1and2are perfect substitutes. 15.A person with the utility function U(x1,x2)=min{x1+2x2,2x1+x2}has convex but not strictly convex preferences.
16.Max Gross has the utility function U(x,y)=max{x,y}.If the price of x is the same as the price of y,Max will buy equal amounts of x and y.
17.If a consumer does not have convex preferences,then a point of tangency between her indifference curve and her budget line must be an optimal consumption point.
18.Ambro’s utility function is U(x,y)=x+4y1/2.The price of x is$1and the price of y is$2.If his income ris from$100to$150,his consumption of y increas by more than10%but less than50%.
19.Mary Granola’s utility function is U(x,y)=min{x+2y,y+2x}.Mary maximizes her utility subject to a bu
dget constraint.If she choos the bundle(5,6), then the price of x must be exactly twice the price of y.
PartⅡ(Single choice)
1.Billy Bob wants to gain some weight so that he can play football.Billy consumes only milk shakes and spinach.Milk shakes cost him$1each and spinach costs$2per rving.A milk shake has850calories and a rving of spinach has200calories.Billy Bob never spends more than$20 a day on food and he always consumes at least8,000calories per day.Which of the following is necessarily true?
a.Billy Bob consumes at least9milk shakes a day.
b.Billy Bob never consumes more than6rvings of spinach a day.
c.Billy Bob never consumes positive amounts of both goods.
d.Billy Bob consumes only milk shakes.
e.None of the above.
2.If you have an income of$40to spend,commodity1costs$4per unit,and commodity2 costs$8per unit,then the equation for your budget line can be written
a.x1/4+x2/8=40.
b.(x1+x2)/12=40.
c.x1+2x2=10.
d.5x1+9x2=41.
e.12(x1+x2)=40.
3.If you could exactly afford either5units of x and21units of y,or9units of x and5 units of y,then if you spent all of your income on y,how many units of y could you buy?
a.57
b.14
c.25
d.41
e.None of the above.
4.Murphy ud to consume100units of X and50units of Y when the price of X was$2and the price of Y was$4.If the price of X ro to$4and the price of Y ro to$9,how much would Murphy’s income have to ri so that he could still afford his original bundle?
a.$700
b.$450
c.$350
d.$1,050
e.None of the above.
5.Suppo there are two goods,the prices of both goods are positive,and a consumer’s income is also positive.If the consumer’s income doubles and the price of both goods triple,
a.the consumer’s budget line gets steeper and shifts inward.
b.the slope of the consumer’s budget line does not change but the budget line shifts outward away from the origin.
c.the consumer’s budget line gets steeper and shifts outwar
李白的诗有哪些d.
d.the slope of the consumer’s budget line does not change but the budget line shifts inward toward the origin.
e.the consumer’s budget line gets flatter and shifts inward.
6.If there are only two goods,if more of good1is always preferred to less,and if less of good 2is always preferred to more,then indifference curves
a.slope downward.
b.slope upward.
c.may cross.
e.None of the above.
7.Charlie’s indifference curves have the equation x B=constant/x A,where larger constants denote better indifference curves.Charlie strictly prefers the bundle(10,17)to
a.the bundle(11,16).
b.the bundle(17,10).
c.the bundle(12,15).
< than one of the bundles.
< of the bundles.
8.Recall that Tommy Twit’s mother measures the departure of any bundle from her favorite bundle for Tommy by the sum of the absolute values of the differences.Her favorite bundle for Tommy is(2,7),
that is,2cookies and7glass of milk.Tommy’s mother’s indifference curve that pass through the point(c,m)=(4,5)also pass through
送花祝福语简短
a.the point(6,3).
b.the points(2,3),(6,7),and(4,9).
c.the point(2,7).
d.the points(4,7),(2,5),and(2,9).
e.None of the above.
9.I prefer6apples and1orange to5apples and2oranges.My preferences
a.are transitive.
finishesb.are complete.
c.are convex.
d.obey the Law of Demand.
e.None of the above.
10.Ike’s utility function is U(x,y)=25xy.He has12units of good x and8units of good y.Ben’s utility function for the same two goods is U(x,y)=4x+4y.Ben has9units of x and13units of y.
a.Ike prefers Ben’s bundle to his own bundle,but Ben prefers his own bundle to Ike’s.
b.Ben prefers Ike’s bundle to his own,but Ike prefers his own bundle to Ben’s.
c.Each prefers the other’s bundle to his own.
d.Neither prefers the other’s bundle to his own.
e.Since they have different preferences,there is not enough information to determine who envies whom.
11.Tim has preferences reprented by the utility function U(x,y)=min{6x+y,x+2y}.If x is on the horizontal axis and y is on the vertical axis,what is the slope of his indifference curve at the point(8,9)?
a.-6
b.-2/6悲伤的小说
c.-1/2
d.-1/6
e.-8/9
12.Mac’s utility function is U(x,y)=max{2x-y,2y-x}.
a.Mac’s preferences are quasilinear.华为手机如何隐藏应用
b.If Mac has more x than y,any increa in his consumption of y would lower his utility.
c.If Mac has more x than y,a decrea in his consumption of y would rai his utility.
d.Mac always prefers more of each good to less.
e.Goods x and y are perfect substitutes.
13.Raymond’s preferences are reprented by the utility function U(x,y)=x/y if y>0and U(x,y)
=0if y=0.
a.Raymond has indifference curves that are rectangular hyperbolas.
b.Raymond prefers more of each good to less.
c.Raymond has quasilinear preferences.
d.Raymond has a bliss point.
e.Raymond has indifference curves that are upward-sloping straight lines if y>0.
14.Joe Bob’s cousin Peter consumes goods1and2.Peter thinks that4units of good1is always a perfect substitute for2units of good2.Which of the following utility functions is the only one that would not reprent Peter’s preferences?
a.U(x1,x2)=min{2x1,4x2}.
b.U(x1,x2)=20x1+40x2-10,000.
c.U(x1,x2)=2x1+4x2+1,000.
d.U(x1,x2)=4x21+16x1x2+16x22.
e.More than one of the above does not reprent Peter’s preferences.
15.Wanda Littlemore’s utility function is U(x,y)=x+46y-2y2.Her income is$135.If the price of x is$1and the price of y is$18,how many units of good x will Wanda demand?
a.5
b.12形容人
c.16
d.0
e.9
16.Janet consumes two commodities x and y.Her utility function is min{x+2y,y+2x}.She choos to buy10units of good x and20units of good y.The price of good x is$1.Janet’s income is
a.$40.
b.$50.
c.$30.
d.$20.
e.There is not enough information in the problem to determine her income becau we are not told the price of good y.
17.Howard has the utility function U(x,y)=x-(1/y).His income is$30.
a.Howard does not like good y.
b.Howard has a bliss point.
c.If the price of good x is$4and the price of good y is$1,Howard will buy2units of y.
d.Howard will buy good y only if it is cheaper than good x.
e.None of the above.
18.Elmer’s utility function is U(x,y)=min{x,y2}.If the price of x is$25and the price of y is$15 and if Elmer choos to consume7units of y,what must his income be?
a.$2,660
b.$280
c.$1,430
d.$1,330
e.There is not enough information to determine his income.
PartⅢ(Problems)
1.Brenda likes hot dogs and Coca-Cola.Hot dogs cost$1each and Cokes cost$.50per bottle. There is a special promotion for Coke that will last for one month.If Brenda nds in the bottle tops from the Cokes she drinks during the next month,she will get a refund of$.20for every bottlecap beyond the first12that she returns.For example,if she returns25bottle caps she will get back$男人爱你的表现
2.60=$.20(25-12).Brenda has$40to spend on hot dogs and Coke during the next month.Draw her budget line with Coke on the horizontal axis and hot dogs on the vertical axis. Find the points where the budget line hits the axes and the point where it has a kink.At each of the three points write down the quantities of each good consumed.
2.Coach Steroid likes his players to be big,fast,and obedient.If player A is better than player B in two of the three characteristics,Steroid will prefer A to B.Three players try out for quarterback.Wilbur Westinghou weighs320pounds,runs very slowly,and is quite obedient. Harold Hotpoint weighs240pounds,runs extremely fast,and is extremely disobedient.Jerry Jacuzzi weighs150pounds,runs at average speed,and is extremely obedient.Does Coach Steroid have transitive preferences?Explain your answer.
3.Max has the utility function U(x,y)=x(y+1).The price of x is$2and the price of y is$1. Income is$10.How much x does Max demand?How much y?If his income doubles and prices stay unchanged,will Max’s demand for both goods double?
4.U parate graphs to draw indifference curves for each of the following utility functions:
a.U(x,y)=min{2x+y,2y+x}.
b.U(x,y)=max{2x+y,2y+x}.
c.U(x,y)=x+min{x,y}.
In which of the cas are preferences convex?
5.Les has the utility function U(x,y)=(x+1)(y+4).The price of y is$1.Les spends all of his income to buy6units of y and no x.What must the price of x be?Explain your answer and draw a diagram to illustrate it.
