ECON210 Intermediate Microeconomics Practice Exam Study Guide Updated 2026 |
Verified Questions and Answers with Detailed Rationales | Consumer Theory and
Utility Maximization, Indifference Curves and Budget Constraints, Producer Theory
and Cost Functions, Market Structures (Perfect Competition, Monopoly,
Monopolistic Competition, Oligopoly), Game Theory and Strategic Behavior,
Elasticity and Demand Analysis, Welfare Economics and Market Efficiency,
Externalities and Public Goods, Mathematical Economics Applications | Complete
Exam Prep Resource for Economics Students Success
Question 1: In consumer theory, the marginal rate of substitution (MRS) between
two goods is best defined as:
A. The ratio of the prices of the two goods
B. The amount of one good a consumer is willing to give up to obtain one more unit of
another good while maintaining the same level of utility
C. The slope of the budget constraint
D. The total utility derived from consuming both goods
CORRECT ANSWER: B. The amount of one good a consumer is willing to give up to
obtain one more unit of another good while maintaining the same level of utility
RATIONALE: The MRS reflects the trade-off a consumer is willing to make between two
goods along an indifference curve, holding utility constant. It is equal to the negative of
the slope of the indifference curve and diminishes as one moves down the curve due to
diminishing marginal utility.
Question 2: If a consumer’s preferences are strictly convex, then their indifference
curves are:
A. Linear
B. L-shaped
C. Bowed inward toward the origin
D. Bowed outward away from the origin
CORRECT ANSWER: C. Bowed inward toward the origin
RATIONALE: Strictly convex preferences imply that the consumer prefers averages to
extremes, which results in indifference curves that are convex to the origin (i.e., bowed
inward). This shape reflects a diminishing marginal rate of substitution.
Question 3: A Giffen good is characterized by:
A. A positive income effect that outweighs a negative substitution effect
B. A negative income effect that outweighs a positive substitution effect
C. An upward-sloping demand curve due to a strong positive substitution effect
D. Being a luxury good with high income elasticity
CORRECT ANSWER: A. A positive income effect that outweighs a negative
substitution effect
,RATIONALE: A Giffen good is an inferior good for which the income effect (positive when
price rises, because real income falls) dominates the substitution effect (which always
works to reduce consumption when price rises), leading to higher quantity demanded
as price increases—hence an upward-sloping demand curve.
Question 4: Which of the following best describes a Cobb-Douglas utility function?
A. U(x, y) = min{ax, by}
B. U(x, y) = x + y
C. U(x, y) = x^α y^(1−α), where 0 < α < 1
D. U(x, y) = x^2 + y^2
CORRECT ANSWER: C. U(x, y) = x^α y^(1−α), where 0 < α < 1
RATIONALE: The Cobb-Douglas utility function exhibits constant expenditure shares
and diminishing marginal rates of substitution. It is widely used due to its analytical
tractability and realistic representation of consumer behavior.
Question 5: The income-consumption curve traces:
A. Optimal bundles as the price of one good changes
B. Optimal bundles as income changes, holding prices constant
C. Combinations of goods that yield the same utility
D. All affordable bundles at different income levels
CORRECT ANSWER: B. Optimal bundles as income changes, holding prices
constant
RATIONALE: The income-consumption curve shows how a consumer’s optimal
consumption bundle changes with income, assuming prices remain unchanged. It is
derived by connecting points of tangency between budget lines and indifference curves
at varying income levels.
Question 6: If two goods are perfect substitutes, the indifference curves are:
A. Concave to the origin
B. Convex to the origin
C. Right angles
D. Straight lines
CORRECT ANSWER: D. Straight lines
RATIONALE: Perfect substitutes imply a constant marginal rate of substitution,
meaning the consumer is always willing to trade one good for the other at a fixed rate.
This yields linear indifference curves.
Question 7: The substitution effect of a price change always:
A. Moves consumption toward the cheaper good
B. Is positive for normal goods
, C. Depends on whether the good is inferior or normal
D. Increases total utility
CORRECT ANSWER: A. Moves consumption toward the cheaper good
RATIONALE: The substitution effect isolates the change in consumption due to relative
price changes, holding utility constant. It always leads the consumer to substitute
toward the now relatively cheaper good, regardless of whether the good is normal or
inferior.
Question 8: In the Slutsky decomposition, the total effect of a price change is
broken into:
A. Income effect and price effect
B. Substitution effect and wealth effect
C. Substitution effect and income effect
D. Compensated and uncompensated effects
CORRECT ANSWER: C. Substitution effect and income effect
RATIONALE: The Slutsky equation decomposes the total effect of a price change into a
substitution effect (change in demand due to relative price change, compensating
income to keep original purchasing power) and an income effect (change due to altered
real income).
Question 9: Which of the following is true about the Hicksian (compensated)
demand curve?
A. It includes both income and substitution effects
B. It is always steeper than the Marshallian demand curve
C. It holds utility constant
D. It is derived from utility maximization without budget constraints
CORRECT ANSWER: C. It holds utility constant
RATIONALE: Hicksian demand minimizes expenditure to achieve a fixed utility level,
thus isolating the substitution effect. It holds utility constant, unlike Marshallian
demand, which holds nominal income constant.
Question 10: If a consumer spends all their income on two goods and the price of
one good doubles while income also doubles, the budget line will:
A. Pivot inward
B. Shift outward parallelly
C. Remain unchanged
D. Become steeper
CORRECT ANSWER: C. Remain unchanged
RATIONALE: If both income and the price of one good double, the intercepts of the
budget line remain the same: the maximum quantity of the good whose price doubled is
Verified Questions and Answers with Detailed Rationales | Consumer Theory and
Utility Maximization, Indifference Curves and Budget Constraints, Producer Theory
and Cost Functions, Market Structures (Perfect Competition, Monopoly,
Monopolistic Competition, Oligopoly), Game Theory and Strategic Behavior,
Elasticity and Demand Analysis, Welfare Economics and Market Efficiency,
Externalities and Public Goods, Mathematical Economics Applications | Complete
Exam Prep Resource for Economics Students Success
Question 1: In consumer theory, the marginal rate of substitution (MRS) between
two goods is best defined as:
A. The ratio of the prices of the two goods
B. The amount of one good a consumer is willing to give up to obtain one more unit of
another good while maintaining the same level of utility
C. The slope of the budget constraint
D. The total utility derived from consuming both goods
CORRECT ANSWER: B. The amount of one good a consumer is willing to give up to
obtain one more unit of another good while maintaining the same level of utility
RATIONALE: The MRS reflects the trade-off a consumer is willing to make between two
goods along an indifference curve, holding utility constant. It is equal to the negative of
the slope of the indifference curve and diminishes as one moves down the curve due to
diminishing marginal utility.
Question 2: If a consumer’s preferences are strictly convex, then their indifference
curves are:
A. Linear
B. L-shaped
C. Bowed inward toward the origin
D. Bowed outward away from the origin
CORRECT ANSWER: C. Bowed inward toward the origin
RATIONALE: Strictly convex preferences imply that the consumer prefers averages to
extremes, which results in indifference curves that are convex to the origin (i.e., bowed
inward). This shape reflects a diminishing marginal rate of substitution.
Question 3: A Giffen good is characterized by:
A. A positive income effect that outweighs a negative substitution effect
B. A negative income effect that outweighs a positive substitution effect
C. An upward-sloping demand curve due to a strong positive substitution effect
D. Being a luxury good with high income elasticity
CORRECT ANSWER: A. A positive income effect that outweighs a negative
substitution effect
,RATIONALE: A Giffen good is an inferior good for which the income effect (positive when
price rises, because real income falls) dominates the substitution effect (which always
works to reduce consumption when price rises), leading to higher quantity demanded
as price increases—hence an upward-sloping demand curve.
Question 4: Which of the following best describes a Cobb-Douglas utility function?
A. U(x, y) = min{ax, by}
B. U(x, y) = x + y
C. U(x, y) = x^α y^(1−α), where 0 < α < 1
D. U(x, y) = x^2 + y^2
CORRECT ANSWER: C. U(x, y) = x^α y^(1−α), where 0 < α < 1
RATIONALE: The Cobb-Douglas utility function exhibits constant expenditure shares
and diminishing marginal rates of substitution. It is widely used due to its analytical
tractability and realistic representation of consumer behavior.
Question 5: The income-consumption curve traces:
A. Optimal bundles as the price of one good changes
B. Optimal bundles as income changes, holding prices constant
C. Combinations of goods that yield the same utility
D. All affordable bundles at different income levels
CORRECT ANSWER: B. Optimal bundles as income changes, holding prices
constant
RATIONALE: The income-consumption curve shows how a consumer’s optimal
consumption bundle changes with income, assuming prices remain unchanged. It is
derived by connecting points of tangency between budget lines and indifference curves
at varying income levels.
Question 6: If two goods are perfect substitutes, the indifference curves are:
A. Concave to the origin
B. Convex to the origin
C. Right angles
D. Straight lines
CORRECT ANSWER: D. Straight lines
RATIONALE: Perfect substitutes imply a constant marginal rate of substitution,
meaning the consumer is always willing to trade one good for the other at a fixed rate.
This yields linear indifference curves.
Question 7: The substitution effect of a price change always:
A. Moves consumption toward the cheaper good
B. Is positive for normal goods
, C. Depends on whether the good is inferior or normal
D. Increases total utility
CORRECT ANSWER: A. Moves consumption toward the cheaper good
RATIONALE: The substitution effect isolates the change in consumption due to relative
price changes, holding utility constant. It always leads the consumer to substitute
toward the now relatively cheaper good, regardless of whether the good is normal or
inferior.
Question 8: In the Slutsky decomposition, the total effect of a price change is
broken into:
A. Income effect and price effect
B. Substitution effect and wealth effect
C. Substitution effect and income effect
D. Compensated and uncompensated effects
CORRECT ANSWER: C. Substitution effect and income effect
RATIONALE: The Slutsky equation decomposes the total effect of a price change into a
substitution effect (change in demand due to relative price change, compensating
income to keep original purchasing power) and an income effect (change due to altered
real income).
Question 9: Which of the following is true about the Hicksian (compensated)
demand curve?
A. It includes both income and substitution effects
B. It is always steeper than the Marshallian demand curve
C. It holds utility constant
D. It is derived from utility maximization without budget constraints
CORRECT ANSWER: C. It holds utility constant
RATIONALE: Hicksian demand minimizes expenditure to achieve a fixed utility level,
thus isolating the substitution effect. It holds utility constant, unlike Marshallian
demand, which holds nominal income constant.
Question 10: If a consumer spends all their income on two goods and the price of
one good doubles while income also doubles, the budget line will:
A. Pivot inward
B. Shift outward parallelly
C. Remain unchanged
D. Become steeper
CORRECT ANSWER: C. Remain unchanged
RATIONALE: If both income and the price of one good double, the intercepts of the
budget line remain the same: the maximum quantity of the good whose price doubled is
