Question

8. , which of the following statements is (are) correct?
(x) The marginal cost of the fifth unit equals the variable cost of five units minus the variable cost of four units
(y) The variable cost of 50 units equals the average variable cost of 50 units times 50.
(z) If marginal cost is rising, then average variable cost is rising if marginal cost exceeds average variable cost.
A. (x), (y) and (z)
B. (x) and (y) only
C. (x) and (z) only
D. (y) and (z) only
E. (x) only

9. Average total cost is increasing whenever
(x) total cost is increasing.
(y) marginal cost exceeds average total cost
(z) marginal cost is increasing.
A. (x), (y) and (z)
B. (x) and (y) only
C. (x) and (z) only
D. (y) and (z) only
E. (y) only

10. Which of the following statements is (are) correct?
(x) A firm has a fixed cost of $10,000 in its first year of operation. When the firm produces 1,000 units of output, its total costs are $72,400. When it produces 1,001 units of output, its total costs are $72,900. The marginal cost of producing the 1,001st unit of output is more than $525.
(y) A firm has a fixed cost of $8,000 in its first year of operation. When the firm produces 100 units of output, its variable costs are $25,000. The marginal cost of producing the 101st unit of output is $1,200. The total cost of producing 101 units is $34,200
(z) A firm has a fixed cost of $6,400 in its first year of operation. When the firm produces 600 units of output, its average total cost is $60. The marginal cost of producing the 601st unit of output is $120. The variable cost of producing 601 units is equal to $29,720
A. (x), (y) and (z)
B. (x) and (y) only
C. (x) and (z) only
D. (y) and (z) only
E. (z) only

Answer 1

Answer- 9 The correct option is A.) (x), (y) and (z)

All of the given statements are correct.

Answer-10 The correct option is E.) (y) only

(X) is not correct because ATC can fall even when total cost is increasing.

(Z) is not correct because in some portion when MC is rising , ATC falls.

Answer-11 The correct option is D.) (y) and (z) only

(x) is not correct because marginal cost of producing the 1001st unit of output is $500