Maths for Economists: Multiple Choice Test 1

Reproduced with permission of Hilary Lamaison, Brunel University, ecsthjl@brunel.ac.uk. Hosted by the Economics Network.

EC1011 Mathematics for Economics
Multiple Choice Test 1 for self-assessment

In answering each of the following questions, click the boxes next to each correct answer. More than one may be correct in some cases. Do not guess. There are 15 correct choices in total. The feedback box at the foot of the page will tell you how many of your answers are correct.

Time allowed = 15 minutes. USE OF A CALCULATOR IS UNNECESSARY BUT OPTIONAL.

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, Qd = 10 − P, QS = 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

7: x2 − 4x + 4 =
(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: Qs = 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: