Waec Mathematics 1998 Past Questions and Answers

Question 61:

• WAEC 1998

Evaluate \(3.0\times 10^1 - 2.8\times 10^{-1}\)leaving the answer in standard form

A. \(2\times 10^{-1}\)
B. \(2\times 10^{2}\)
C. \(2.972 \times 10^{1}\)
D. \(2.972 \times 10^{2}\)

Question 62:

• WAEC 1998

A trader makes a loss of 15% when selling an article. Find the ratio, selling price : cost price

A. 3:20
B. 3:17
C. 17:20
D. 20:23

Question 63:

• WAEC 1998

The side of a square is increased from 20cm to 21cm. Calculate the percentage increase in its area

A. 2.5%
B. 9.3%
C. 10.0%
D. 10.25%

Question 64:

• WAEC 1998

Arrange in ascending order of magnitude \(26_8, 36_7, and 25_9\)

A. \(25_9 26_8 36_7\)
B. \(26_8 25_9 36_7\)
C. \(36_7 26_8 25_9\)
D. \(36_7 25_9 26_8\)

Question 65:

• WAEC 1998

A, B and C are subsets of the universal set U such that : \(U = {0, 1, 2, 3,..., 12}; A = {x : 0 \leq x \leq 7}; B = {4, 6, 8, 10, 12}; C = {1 < y < 8}\), where y is a prime number.
(a) Draw a venn diagram to illustrate the information given above;
(b) Find: (i) \((B \cup C)'\); (ii) \(A' \cap B \cap C\).