Year : 
2001
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

11 - 20 of 49 Questions

# Question Ans
11.

Evaluate \(\frac{1}{2}+\frac{3}{4}of\frac{2}{5}\div 1\frac{3}{5}\)

A. \(\frac{15}{16}\)

B. \(\frac{11}{16}\)

C. \(\frac{49}{50}\)

D. \(3\frac{1}{5}\)

Detailed Solution

\(\frac{1}{2} + (\frac{3}{4} \text{ of } \frac{2}{5}) \div 1\frac{3}{5}\)
= \(\frac{1}{2} + (\frac{3}{4} \times \frac{2}{5}) \div \frac{8}{5}\)
= \(\frac{1}{2} + \frac{3}{10} \div \frac{8}{5}\)
= \(\frac{1}{2} + (\frac{3}{10} \times \frac{5}{8})\)
= \(\frac{1}{2} + \frac{3}{16}\)
= \(\frac{11}{16}\)
12.

A man is four times as old as his son. The difference between their ages is 36 years Find the sum of their ages

A. 45 years

B. 48 years

C. 60 years

D. 74 years

Detailed Solution

Let the sons age be x. The father is 4x
∴ 4x - x = 36; 3x = 36; x = 12
The son is 12 years and the father is 12 x 4 = 48.
The sum of their ages (12 + 48) years = 60years
13.

Given that y = px + q and y = 5 when x = 3, while y = 4 when x = 2, find the value of p and q.

A. p = 1, q = 3

B. p = 1, q = 2

C. p = -2, q = 3

D. p = 3, q = -2

Detailed Solution

y = px + q
5 = 3p + q ... (i)
4 = 2p + q ... (ii)
(i) - (ii) : p = 1
\(\therefore\) 5 = 3(1) + q
\(\implies\) q = 5 - 3 = 2
(p, q) = (1, 2)
14.

Evaluate \(\frac{x^2 + x - 2}{2x^2 + x -3}\) when x = -1

A. -2

B. -1

C. \(-\frac{1}{2}\)

D. 1

Detailed Solution

\(\frac{x^2 + x - 2}{2x^2 + x - 3}\)
= \(\frac{x^2 + 2x - x - 2}{2x^2 + 3x - 2x - 3}\)
= \(\frac{x(x + 2) - 1(x + 2)}{x(2x + 3) - 1(2x + 3)}\)
= \(\frac{(x - 1)(x + 2)}{(x - 1)(2x + 3)}\)
= \(\frac{x + 2}{2x + 3}\)
At x = -1,
= \(\frac{-1 + 2}{2(-1) + 3}\)
= \(\frac{1}{1}\)
= 1
15.

Factorize \(6x^2 + 7x - 20\)

A. (6x - 5)(x + 4)

B. 2(3x-5)(x+2)

C. (3x+4)(2x-5)

D. (3x-4)(2x+5)

Detailed Solution

\(6x^2 + 7x - 20\)
= \(6x^2 + 15x - 8x - 20\)
= \(3x(2x + 5) - 4(2x + 5)\)
= \((3x - 4)(2x + 5)\)
16.

Simplify \(\frac{2x-1}{3}-\frac{x+3}{2}\)

A. \(\frac{x+3}{6}\)

B. \(\frac{x+8}{6}\)

C. \(\frac{x-11}{6}\)

D. \(\frac{x-4}{6}\)

Detailed Solution

\(\frac{2x - 1}{3} - \frac{x + 3}{2}\)
= \(\frac{2(2x - 1) - 3(x + 3)}{6}\)
= \(\frac{4x - 2 - 3x - 9}{6}\)
= \(\frac{x - 11}{6}\)
17.

If \(\frac{y-3}{2}<\frac{2y-1}{3}\), which of the following is true?

A. y > 7

B. y < -7

C. y > -7

D. y < 7

Detailed Solution

\(\frac{y - 3}{2} < \frac{2y - 1}{3}\)
\(3(y - 3) < 2(2y - 1)\)
\(3y - 9 < 4y - 2\)
\(3y - 4y < -2 + 9\)
\(-y < 7\)
\(y > -7\)
18.

If \(\frac{4m+3n}{4m-3n}=\frac{5}{2}\), find the ratio m:n

A. 7:4

B. 4:3

C. 3:4

D. 4:7

Detailed Solution

\(\frac{4m + 3n}{4m - 3n} = \frac{5}{2}\)
\(5(4m - 3n) = 2(4m + 3n)\)
\(20m - 15n = 8m + 6n\)
\(20m - 8m = 6n + 15n\)
\(12m = 21n\)
\(\frac{21}{12} = \frac{m}{n}\)
\(m : n = 7 : 4\)
19.

If \(2x^2 + kx - 14 = (x+2)(2x-7)\), find the value of K

A. -3

B. 5

C. 9

D. 11

Detailed Solution

\(2x^2 + kx - 14 = (x+2)(2x-7)\\
∴2x^2 + kx - 14 = 2x^2 - 3x - 14\)
equating coefficient K = -3
20.

Which of the following is not quadratic expression?

A. \(y = 2x^2 - 5x\)

B. \(y=x(x-5)\)

C. \(y = x^2 - 5\)

D. y = 5(x-1)

Detailed Solution

A quadratic equation is an equation of the second order. The highest power in the equation is 2.
11.

Evaluate \(\frac{1}{2}+\frac{3}{4}of\frac{2}{5}\div 1\frac{3}{5}\)

A. \(\frac{15}{16}\)

B. \(\frac{11}{16}\)

C. \(\frac{49}{50}\)

D. \(3\frac{1}{5}\)

Detailed Solution

\(\frac{1}{2} + (\frac{3}{4} \text{ of } \frac{2}{5}) \div 1\frac{3}{5}\)
= \(\frac{1}{2} + (\frac{3}{4} \times \frac{2}{5}) \div \frac{8}{5}\)
= \(\frac{1}{2} + \frac{3}{10} \div \frac{8}{5}\)
= \(\frac{1}{2} + (\frac{3}{10} \times \frac{5}{8})\)
= \(\frac{1}{2} + \frac{3}{16}\)
= \(\frac{11}{16}\)
12.

A man is four times as old as his son. The difference between their ages is 36 years Find the sum of their ages

A. 45 years

B. 48 years

C. 60 years

D. 74 years

Detailed Solution

Let the sons age be x. The father is 4x
∴ 4x - x = 36; 3x = 36; x = 12
The son is 12 years and the father is 12 x 4 = 48.
The sum of their ages (12 + 48) years = 60years
13.

Given that y = px + q and y = 5 when x = 3, while y = 4 when x = 2, find the value of p and q.

A. p = 1, q = 3

B. p = 1, q = 2

C. p = -2, q = 3

D. p = 3, q = -2

Detailed Solution

y = px + q
5 = 3p + q ... (i)
4 = 2p + q ... (ii)
(i) - (ii) : p = 1
\(\therefore\) 5 = 3(1) + q
\(\implies\) q = 5 - 3 = 2
(p, q) = (1, 2)
14.

Evaluate \(\frac{x^2 + x - 2}{2x^2 + x -3}\) when x = -1

A. -2

B. -1

C. \(-\frac{1}{2}\)

D. 1

Detailed Solution

\(\frac{x^2 + x - 2}{2x^2 + x - 3}\)
= \(\frac{x^2 + 2x - x - 2}{2x^2 + 3x - 2x - 3}\)
= \(\frac{x(x + 2) - 1(x + 2)}{x(2x + 3) - 1(2x + 3)}\)
= \(\frac{(x - 1)(x + 2)}{(x - 1)(2x + 3)}\)
= \(\frac{x + 2}{2x + 3}\)
At x = -1,
= \(\frac{-1 + 2}{2(-1) + 3}\)
= \(\frac{1}{1}\)
= 1
15.

Factorize \(6x^2 + 7x - 20\)

A. (6x - 5)(x + 4)

B. 2(3x-5)(x+2)

C. (3x+4)(2x-5)

D. (3x-4)(2x+5)

Detailed Solution

\(6x^2 + 7x - 20\)
= \(6x^2 + 15x - 8x - 20\)
= \(3x(2x + 5) - 4(2x + 5)\)
= \((3x - 4)(2x + 5)\)
16.

Simplify \(\frac{2x-1}{3}-\frac{x+3}{2}\)

A. \(\frac{x+3}{6}\)

B. \(\frac{x+8}{6}\)

C. \(\frac{x-11}{6}\)

D. \(\frac{x-4}{6}\)

Detailed Solution

\(\frac{2x - 1}{3} - \frac{x + 3}{2}\)
= \(\frac{2(2x - 1) - 3(x + 3)}{6}\)
= \(\frac{4x - 2 - 3x - 9}{6}\)
= \(\frac{x - 11}{6}\)
17.

If \(\frac{y-3}{2}<\frac{2y-1}{3}\), which of the following is true?

A. y > 7

B. y < -7

C. y > -7

D. y < 7

Detailed Solution

\(\frac{y - 3}{2} < \frac{2y - 1}{3}\)
\(3(y - 3) < 2(2y - 1)\)
\(3y - 9 < 4y - 2\)
\(3y - 4y < -2 + 9\)
\(-y < 7\)
\(y > -7\)
18.

If \(\frac{4m+3n}{4m-3n}=\frac{5}{2}\), find the ratio m:n

A. 7:4

B. 4:3

C. 3:4

D. 4:7

Detailed Solution

\(\frac{4m + 3n}{4m - 3n} = \frac{5}{2}\)
\(5(4m - 3n) = 2(4m + 3n)\)
\(20m - 15n = 8m + 6n\)
\(20m - 8m = 6n + 15n\)
\(12m = 21n\)
\(\frac{21}{12} = \frac{m}{n}\)
\(m : n = 7 : 4\)
19.

If \(2x^2 + kx - 14 = (x+2)(2x-7)\), find the value of K

A. -3

B. 5

C. 9

D. 11

Detailed Solution

\(2x^2 + kx - 14 = (x+2)(2x-7)\\
∴2x^2 + kx - 14 = 2x^2 - 3x - 14\)
equating coefficient K = -3
20.

Which of the following is not quadratic expression?

A. \(y = 2x^2 - 5x\)

B. \(y=x(x-5)\)

C. \(y = x^2 - 5\)

D. y = 5(x-1)

Detailed Solution

A quadratic equation is an equation of the second order. The highest power in the equation is 2.