Year : 
2000
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

31 - 40 of 48 Questions

# Question Ans
31.

Simplify \(\frac{1}{x-3}-\frac{3(x-1)}{x^2 - 9}\)

A. \(\frac{x-1}{x-3}\)

B. \(\frac{-2}{x+3}\)

C. \(\frac{x-1}{x+3}\)

D. \(\frac{4x}{x^2-9}\)

Detailed Solution

\(\frac{1}{x-3}-\frac{3(x-1)}{x^2 - 9}\\
\frac{1}{x-3}-\frac{3(x-1)}{(x-3)(x+3)}\\
\frac{x+3-3x+3}{(x-3)(x+3)};\frac{-2x+6}{(x-3)(x+3)}\\
\frac{-2(x-3)}{(x-3)(x+3)}=\frac{-2}{x+3}\)
32.

Form an inequality for a distance d meters which is more than 18m, but not more than 23m

A. 18 ≤ d ≤ 23

B. 18 < d ≤ 23

C. 18 ≤ d < 23

D. d < 18 or d > 23

B

33.

Find the equation whose roots are -8 and 5

A. \(x^2 + 13x + 40=0\)

B. \(x^2 - 13x - 40=0\)

C. \(x^2 - 3x +40=0\)

D. \(x^2 + 3x - 40=0\)

Detailed Solution

Equation with roots -8 and 5: (x + 8)(x - 5) = 0
\(x^2 - 5x + 8x - 40 = 0\)
\(x^2 + 3x - 40 = 0\)
34.

Make t the subject of formula \(k = m\sqrt{\frac{t-p}{r}}\)

A. \(\frac{rk^2 + p}{m^2}\)

B. \(\frac{rk^2+pm^2}{m^2}\)

C. \(\frac{rk^2-p}{m^2}\)

D. \(\frac{rk^2-p^2}{m^2}\)

Detailed Solution

\(k = m\sqrt{\frac{t - p}{r}}\)
\(\frac{k}{m} = \sqrt{\frac{t - p}{r}}\)
\((\frac{k}{m})^2 = \frac{t - p}{r}\)
\(rk^2 = m^2 (t - p)\)
\(\therefore m^2 t = rk^2 + m^2 p\)
\(t = \frac{rk^2 + m^2 p}{m^2}\)
35.

Solve the equation \(3y^2 = 27y\)

A. y = o or 3

B. y = 0 or 9

C. y = -3 or 3

D. y = 3 or 9

Detailed Solution

\(3y^2 = 27y\\
3y^2 - 27y = 0\\
3y(y - 9) = 0\\
3y = 0 or y - 9 = 0\\
y = 0 or y = 9\\
y = 0 or 9\)
36.

Find the value of x such that the expression \(\frac{1}{x}+\frac{4}{3x}-\frac{5}{6x}+1\) equals zero

A. \(\frac{1}{6}\)

B. \(\frac{1}{4}\)

C. \(\frac{-3}{2}\)

D. \(\frac{-7}{6}\)

Detailed Solution

\(\frac{1}{x} + \frac{4}{3x} - \frac{5}{6x} + 1 = 0\)
\(\frac{6 + 8 - 5 + 6x}{6x} = 0\)
\(\frac{9 + 6x}{6x} = 0 \implies 9 + 6x = 0\)
\(6x = -9 \implies x = \frac{-3}{2}\)
37.

Given that p varies directly as q while q varies inversely as r, which of the following statements is true?

A. r varies directly as p

B. p varies inversely as r

C. p varies directly as r

D. q varies inversely as p

B

38.

In the diagram, PQS is a circle with center O. RST is a tangent at S and ∠SOP = 96o. Find ∠PST

A. 42o

B. 48o

C. 60o

D. 66o

B

39.

A bicycle wheel of radius 42cm is rolled over a distance 66 meters. How many revolutions does it make?[Take \(\pi = \frac{22}{7}\)]

A. 2.5

B. 5

C. 25

D. 50

Detailed Solution

circumference of the bicycle wheel
\(= 2\pi r = 2 \times \frac{22}{7} \times 42 - 264cm = 2.64m\\\)
Number of revolution
\(=\frac{66}{2.64} = 25\)
40.

The height of a pyramid on square base is 15cm. if the volume is 80cm^3, find the area of the square base.

A. 8cm2

B. 9.6cm2

C. 16cm2

D. 25cm2

Detailed Solution

Volume of pyramid with square base = \(\frac{\text{base area} \times height}{3}\)
\(80 = \frac{\text{base area} \times 15}{3}\)
\(80 = 5 \times \text{base area}\)
\(\text{Base area} = 16 cm^2\)
31.

Simplify \(\frac{1}{x-3}-\frac{3(x-1)}{x^2 - 9}\)

A. \(\frac{x-1}{x-3}\)

B. \(\frac{-2}{x+3}\)

C. \(\frac{x-1}{x+3}\)

D. \(\frac{4x}{x^2-9}\)

Detailed Solution

\(\frac{1}{x-3}-\frac{3(x-1)}{x^2 - 9}\\
\frac{1}{x-3}-\frac{3(x-1)}{(x-3)(x+3)}\\
\frac{x+3-3x+3}{(x-3)(x+3)};\frac{-2x+6}{(x-3)(x+3)}\\
\frac{-2(x-3)}{(x-3)(x+3)}=\frac{-2}{x+3}\)
32.

Form an inequality for a distance d meters which is more than 18m, but not more than 23m

A. 18 ≤ d ≤ 23

B. 18 < d ≤ 23

C. 18 ≤ d < 23

D. d < 18 or d > 23

B

33.

Find the equation whose roots are -8 and 5

A. \(x^2 + 13x + 40=0\)

B. \(x^2 - 13x - 40=0\)

C. \(x^2 - 3x +40=0\)

D. \(x^2 + 3x - 40=0\)

Detailed Solution

Equation with roots -8 and 5: (x + 8)(x - 5) = 0
\(x^2 - 5x + 8x - 40 = 0\)
\(x^2 + 3x - 40 = 0\)
34.

Make t the subject of formula \(k = m\sqrt{\frac{t-p}{r}}\)

A. \(\frac{rk^2 + p}{m^2}\)

B. \(\frac{rk^2+pm^2}{m^2}\)

C. \(\frac{rk^2-p}{m^2}\)

D. \(\frac{rk^2-p^2}{m^2}\)

Detailed Solution

\(k = m\sqrt{\frac{t - p}{r}}\)
\(\frac{k}{m} = \sqrt{\frac{t - p}{r}}\)
\((\frac{k}{m})^2 = \frac{t - p}{r}\)
\(rk^2 = m^2 (t - p)\)
\(\therefore m^2 t = rk^2 + m^2 p\)
\(t = \frac{rk^2 + m^2 p}{m^2}\)
35.

Solve the equation \(3y^2 = 27y\)

A. y = o or 3

B. y = 0 or 9

C. y = -3 or 3

D. y = 3 or 9

Detailed Solution

\(3y^2 = 27y\\
3y^2 - 27y = 0\\
3y(y - 9) = 0\\
3y = 0 or y - 9 = 0\\
y = 0 or y = 9\\
y = 0 or 9\)
36.

Find the value of x such that the expression \(\frac{1}{x}+\frac{4}{3x}-\frac{5}{6x}+1\) equals zero

A. \(\frac{1}{6}\)

B. \(\frac{1}{4}\)

C. \(\frac{-3}{2}\)

D. \(\frac{-7}{6}\)

Detailed Solution

\(\frac{1}{x} + \frac{4}{3x} - \frac{5}{6x} + 1 = 0\)
\(\frac{6 + 8 - 5 + 6x}{6x} = 0\)
\(\frac{9 + 6x}{6x} = 0 \implies 9 + 6x = 0\)
\(6x = -9 \implies x = \frac{-3}{2}\)
37.

Given that p varies directly as q while q varies inversely as r, which of the following statements is true?

A. r varies directly as p

B. p varies inversely as r

C. p varies directly as r

D. q varies inversely as p

B

38.

In the diagram, PQS is a circle with center O. RST is a tangent at S and ∠SOP = 96o. Find ∠PST

A. 42o

B. 48o

C. 60o

D. 66o

B

39.

A bicycle wheel of radius 42cm is rolled over a distance 66 meters. How many revolutions does it make?[Take \(\pi = \frac{22}{7}\)]

A. 2.5

B. 5

C. 25

D. 50

Detailed Solution

circumference of the bicycle wheel
\(= 2\pi r = 2 \times \frac{22}{7} \times 42 - 264cm = 2.64m\\\)
Number of revolution
\(=\frac{66}{2.64} = 25\)
40.

The height of a pyramid on square base is 15cm. if the volume is 80cm^3, find the area of the square base.

A. 8cm2

B. 9.6cm2

C. 16cm2

D. 25cm2

Detailed Solution

Volume of pyramid with square base = \(\frac{\text{base area} \times height}{3}\)
\(80 = \frac{\text{base area} \times 15}{3}\)
\(80 = 5 \times \text{base area}\)
\(\text{Base area} = 16 cm^2\)