Maths for Economists: Multiple Choice Test 1

1: Which of the following is true?

0.6 is an irrational number
-1/6 is a rational number
√(-4) is a real number
5 ∉ J

2: (x + y)(x - y) =

x² + 2xy − y²
x² − 2xy + y²
x² − y²
x² + yx − y²

3:  x  +  2x   =
    x-1   x+3

3x² + x
    (x−1)(x+3)
 3x   
    (x−1)(x+3)
 3x  
    2x + 2
x² + 3 + 2x
     (x−1)(x+3)

4: If y = 3 − 1.5 x, which of the following are true?

x = y − 3
            1.5
1.5x + y = 3
3x + 2y = 6
y − 1.5x = 3

5: For the demand and supply functions, Q_d = 10 − P, Q_S = 3P − 2, the equilibrium (P₀,Q₀) is:

(6,4)
(5,5)
(7,3)
(3,7)

6: A firm with total costs TC = 50 + 3Q for Q units of output, which sells its output at price P = 5, breaks even at the output level:

Q = 50/3
Q = 50/8
Q = 50/2
Q = 45/3

(x − 2)²
(x − 2)(x − 2)
(x − 2)(x + 2)
(x − 4)²

8: x² + 7x + 12 = 0 implies:

x = 6 or x = -2
x = 4 or x = 3
x = -4 or x = -3
x = 6 or x = 2

9: The supply function for a product is given by: Q_s = 3P − 4. A unit tax t is then imposed on the supplier. The new supply function becomes:

Q'_s = 3P − 4 + t
Q'_s = 3(P − t) − 4
Q'_s = 3P − 4 − 3t
Q'_s = 3P − 4 − t

10: For a firm whose total cost and total revenue functions are given by: TC = mQ + c , TR = P.Q which of the following statements is true?

If variable costs per unit (m) increase, the break even point (Q) will fall
If price (P) falls, the break even point will rise
If fixed costs (c) fall, the break even point will fall
If fixed costs (c) rise, the break even point will be unchanged

  Attempts:

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