Practice problem set 2
Managerial Economics
PGP – 1: Term 1, Section A, 2019-2020
1) The assumption of transitive preferences implies that indifference curves must:
A) not cross one another.
B) have a positive slope.
C) be L-shaped.
D) be convex to the origin.
E) all of the above
2) A consumer prefers market basket A to market basket B, and prefers market basket B to
market basket C. Therefore, A is preferred to C. The assumption that leads to this conclusion
is:
A) transitivity.
B) completeness.
C) all goods are good.
D) diminishing MRS.
E) assumption of rationality.
3) The assumption that preferences are complete:
A) means that a consumer will spend her entire income.
B) is unnecessary, as long as transitivity is assumed.
C) recognizes that there may be pairs of market baskets that cannot be compared.
D) means that the consumer can compare any two market baskets of goods and determine
that either one is preferred to the other or that she is indifferent between them.
4) A curve that represents all combinations of market baskets that provide the same level of
utility to a consumer is called:
A) a budget line.
B) an isoquant.
C) an indifference curve.
D) a demand curve.
E) none of the above
5) An upward sloping indifference curve defined over two goods violates which of the
following assumptions from the theory of consumer behavior?
A) transitivity.
B) preferences are complete.
C) more is preferred to less.
D) all of the above
E) none of the above
Alvin's preferences for good X and good Y are shown in the diagram below.
1
Figure 3.1
6) Based on Figure 3.1, it can be inferred that:
A) Alvin does not consider good X as "good."
B) Alvin will never purchase any of good Y.
C) Alvin regards good X and good Y as perfect substitutes.
D) Alvin regards good X and good Y as perfect complements.
E) none of the above
7) Refer to Figure 3.1. Which of the following is true concerning Alvin's marginal rate of
substitution?
A) It is diminishing.
B) It is positive but varies along the indifference curve.
C) It is constant.
D) It is zero.
8) Consider the following three market baskets:
Food Clothing
A 15 18
B 13 19
C 14 17
If baskets B and C are on the same indifference curve, and if preferences satisfy all the basic
assumptions, then:
A) A is preferred to C.
B) A is preferred to B.
C) Both A and B answer choices are correct.
D) none of the above
9) Mikey is very picky and insists that his mom make his breakfast with equal parts of cereal
and apple juice — any other combination and it ends up on the floor. Cereal costs 4 cents per
tablespoon and apple juice costs 6 cents per tablespoon. If Mikey's mom budgets $8 per month
for Mikey's breakfast, how much cereal and juice does she buy?
A) 40 tablespoons each of cereal and juice
2
B) 80 tablespoons each of cereal and juice
C) 40 tablespoons of cereal and 75 tablespoons of juice
D) 100 tablespoons of cereal and 67 tablespoons of juice
10) Jane is trying to decide which courses to take next semester. She has narrowed down her
choice to two courses, Econ 1 and Econ 2. Now she is having trouble and cannot decide which
of the two courses to take. It's not that she is indifferent between the two courses, she just
cannot decide. An economist would say that this is an example of preferences that:
A) are not transitive.
B) are incomplete.
C) violate the assumption that more is preferred to less.
D) all of the above
11) If a consumer is always indifferent between an additional one grapefruit or an additional
two oranges, then when oranges are on the horizontal axis the indifference curves:
A) will be straight lines with a slope of -1/2.
B) will be straight lines with a slope of -1.
C) will be straight lines with a slope of +1/2.
D) will be right angles whose corners occur on a ray from the origin with a slope of +2.
E) none of the above
12) Which of the following statements is true about a consumer's optimal decision when
indifference curves are concave to the origin?
A) Both goods are consumed.
B) No goods are consumed.
C) Only one of the goods is consumed.
D) It occurs at the point of tangency with the budget line.
13) Pencils sell for 10 cents and pens sell for 50 cents. Suppose Jack, whose preferences satisfy
all of the basic assumptions, buys 5 pens and one pencil each semester and spends all income.
With this consumption bundle, his MRS of pencils for pens is 3. Which of the following is
true?
A) Jack could increase his utility by buying more pens and fewer pencils.
B) Jack could increase his utility by buying more pencils and fewer pens.
C) Jack could increase his utility by buying more pencils and more pens.
D) Jack could increase his utility by buying fewer pencils and fewer pens.
E) Jack is at a corner solution and is maximizing his utility.
14) An individual consumes only two goods, X and Y. Which of the following expressions
represents the utility maximizing market basket?
A) MRSxy is at a maximum.
B) Px/Py = money income.
C) MRSxy = money income.
D) MRSxy = Px/Py.
E) all of the above
15) The fact that Alice spends no money on travel:
3
A) implies that she does not derive any satisfaction from travel.
B) implies that she is at a corner solution.
C) implies that her MRS does not equal the price ratio.
D) any of the above are possible.
16) The price of lemonade is $0.50; the price of popcorn is $1.00. If Fred has maximized his
utility by purchasing lemonade and popcorn, his marginal rate of substitution will be:
A) 2 lemonades for each popcorn.
B) 1 lemonades for each popcorn.
C) 1/2 lemonade for each popcorn.
D) indeterminate unless more information on Fred's marginal utilities is provided.
17) If Px = Py, then when the consumer maximizes utility,
A) X must equal Y.
B) MU(X) must equal MU(Y).
C) MU(X) may equal MU(Y), but it is not necessarily so.
D) X and Y must be substitutes.
18) As we move downward along a demand curve for apples,
A) consumer well-being decreases.
B) the marginal utility of apples decreases.
C) the marginal utility of apples increases.
D) Both A and B are true.
E) Both A and C are true.
19) The price of good A goes up. As a result the demand for good B shifts to the left. From
this we can infer that:
A) good A is a normal good.
B) good B is an inferior good.
C) goods A and B are substitutes.
D) goods A and B are complements.
E) none of the above
20) In a recent article, two economists estimated that the 37.5% increase in price that would
result from a 75 cent tax increase on cigarettes would lead to a decrease in smoking among
college students of 30%. What can you conclude about the demand for cigarettes among
college students?
A) It is price elastic.
B) It is price inelastic.
C) It is unit elastic.
D) It is perfectly inelastic.
Scenario 4.2:
Suppose that the demand for artichokes (Qa) is given as:
Qa = 200 - 4P
4
21) Use the information in Scenario 4.2. What is the price elasticity of demand if the price of
artichokes is $10?
A) 0
B) -0.25
C) -1
D) -4
E) negative infinity
22) Use the information in Scenario 4.2. Suppose that the price of artichokes is increased
slightly from $10. The total expenditure by consumers on artichokes will ________ and the
number of artichokes sold will ________.
A) rise, rise
B) rise, fall
C) fall, rise
D) fall, fall
23) Use the information in Scenario 4.2. At what price, if any, is the demand for artichokes
completely or perfectly elastic?
A) 50
B) 30
C) 10
D) 0
E) none of the above
Short answer type:
24) A consumer decides not to buy a VCR when her income is $20,000. However, when her
income rises to $30,000, she decides to buy one. In a single diagram, draw the budget lines
and indifference curves to illustrate this situation (assume the VCR costs $300 in both time
periods). Be sure to label your diagram completely.
25) The following combinations of goods X and Y represent various market baskets.
Consumption is measured in pounds per month.
Market Basket Units of X Units of Y
A 4 6
B 16 7
C 15 3
D 3 2
Explain which market basket(s) is(are) preferred to other(s), and if there is any uncertainty
over which is preferable, point this out as well.
26) The budget constraint for a consumer who only buys apples (A) and bananas (B) is PAA
+ PBB = I where consumer income is I, the price of apples is PA, and the price of bananas is
5
PB. To plot this budget constraint in a figure with apples on the horizontal axis, we should
use a budget line represented by the slope-intercept equation:
A) A = -I/PA + (PB/PA)B
B) A = I/PA - (PB/PA)B
C) B = -I/PB + (PA/PB)A
D) B = I/PB - (PA/PB)A
27) Sally consumes two goods, X and Y. Her utility function is given by the expression
U = 3 · XY2. The current market price for X is $10, while the market price for Y is $5. Sally's
current income is $500.
a. Sketch a set of two indifference curves for Sally in her consumption of X and Y.
b. Write the expression for Sally's budget constraint. Graph the budget constraint and
determine its slope.
c. Determine the X,Y combination which maximizes Sally's utility, given her budget
constraint. Show her optimum point on a graph. (Partial units for the quantities are possible.)
(Note: MUY = 6XY and MUX = 3Y2.)
d. Calculate the impact on Sally's optimum market basket of an increase in the price of X to
$15. What would happen to her utility as a result of the price increase?
28) An individual consumes products X and Y and spends $25 per time period. The prices of
the two goods are $3 per unit for X and $2 per unit for Y. The consumer in this case has a
utility function expressed as:
U(X,Y) = .5XY MUX = .5Y MUY = .5X.
a. Express the budget equation mathematically.
b. Determine the values of X and Y that will maximize utility in the consumption of X and
Y.
c. Determine the total utility that will be generated per unit of time for this individual.
29) Harding Enterprises has developed a new product called the Gillooly shillelagh. The
market demand for this product is given as follows:
Q = 240 - 4P
a. If the shillelagh is priced at $40, what is the point price elasticity of demand? Is demand
elastic or inelastic?
b. If the shillelagh price is increased slightly from $40, what will happen to the total
expenditure on the Gillooly shillelagh?
30) Results from demand function estimation for good A is the following (A and B are two
related goods):
6
Source SS df MS Number of obs = 10
F(3, 6) = 35.52
Model 24299398.6 3 8099799.53 Prob > F = 0.0003
Residual 1368031.51 6 228005.251 R-squared = 0.9467
Adj R-squared = 0.9201
Total 25667430.1 9 2851936.68 Root MSE = 477.5
Quantity_A Coef. Std. Err. t P>|t| [95% Conf. Interval]
Price_A -.0294552 .0043463 -6.78 0.001 -.0400903 -.0188202
Income 3.397679 .9201697 3.69 0.010 1.146105 5.649254
Price_B -42.0614 4.489299 -9.37 0.000 -53.04632 -31.07649
_cons 8485.553 590.7779 14.36 0.000 7039.972 9931.135
a. Write the demand function for A.
b. Are these estimated coefficients statistically different from zero? Explain your answer.
c. Comment on the relationship between good A and good B.
d. Compute the price elasticity of demand for good A at quantity = 4356 and price=140625.
e. Is it elastic or inelastic?
f. What would be the impact on revenue if the producer of A raises its price (from quantity =
4356 and price=140625)?
