Year : 
1995
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

1 - 10 of 48 Questions

# Question Ans
1.

Find (101\(_2\))\(^2\), expressing the answer in base 2.

A. 10101

B. 11001

C. 10010

D. 11101

E. 10110

Detailed Solution

You can convert it to base 10 and square, then re-convert it after the operation.
OR
You can multiply it straight applying the rules of binary multiplication.
2.

If three children shares N10.50 among themselves in ratio 6:7:8, how much is the largest share?

A. N3.00

B. N3.50

C. N4.00

D. N4.50

E. N5.00

Detailed Solution

Ratio = 6 + 7 + 8 = 21
21 = N10.50
1 = 1050K/21 = 50K
6 = 6 x 50K = N3.00
7 = 7 x 50K = N3.50
8 = 8 x 50K = N4.00
the Largest share = N4.00
3.

Express 0.000834 in standard form

A. 8.34 x 10-4

B. 8.34 x 10-3

C. 8.34 x 103

D. 8.34 x 104

E. 8.34 x 106

A

4.

Given that log2a = log84, find a

A. 21/3

B. 42/3

C. 42/3

D. 22/3

E. 23

Detailed Solution

Log2a = Log84
Log2a = Log882/3 → 2/3Log88 → 2/3 x 1
Log2a = 2/3
Recall; If Logax = y ∴ ay = x
Log2a = 2/3
22/3 = a
5.

By selling some crates of soft drinks for N600.00, a dealer makes a profit of 50%. How much did the dealer pay for the drinks?

A. N1,200.00

B. N900.00

C. N450.00

D. N400.00

E. N200.00

Detailed Solution

S.P = N600.00
(100 + 50)% = N600
150% = N600
1% = \(\frac{600}{150}\)
100% = \(\frac{600}{150} \times 100%\)
= N400
6.

Find the nth term Un of the A.P., 11, 4, -3,....... .

A. Un=19+7n

B. Un=19-7n

C. Un=18+7n

D. Un= 18-7n

E. Un= 17-7n

Detailed Solution

A.P 11, 4, -3
1st term = 11
A.P = a, a + d, a + 2d ...... a + (n - 1)d
If a = 11
a + d = 4
d = 4 - 11 = -7
nth term = a + (n-1)d
         = 11 + (n-1)(-7)
         = 11 - 7n + 7
         = 18 - 7n
7.

Lf 16/9 , x, 1, y are in Geometric Progression (GP), find the product of x and y.

A. 9/16

B. 3/4

C. 1

D. 4/3

E. 16/6

Detailed Solution

16/9, x, 1, y => a, ar, ar2, ar3
ar2 = 1 => 16r2/9 = 1 => 16r2
9 => r2 = 9/16 => r = 3/4
ar2 = y = ar2 x r = 1 x 3/4 = 3/4
x xy = 4/3 x 3/4 = 1
8.

If R = [2, 4, 6, 7] and S = [1, 2, 4, 8], then R∪S equal

A. [1,2,4,6,7,8]

B. [1,2,4,7,8]

C. [1,4.7,8]

D. [2.6.7]

E. [2.4]

Detailed Solution

R = {2, 4, 6, 7}; S = {1, 2, 4, 8}
R \(\cup\) S = {1, 2, 4, 6, 7, 8}
9.

Find the value(s) of x for which the expression is undefined: \(\frac{6x - 1}{x^2 + 4x - 5}\)

A. +4 or+1

B. -5 or +1

C. -5 or -1

D. +5 or -1

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

Detailed Solution

\(\frac{6x - 1}{x^2 + 4x - 5}\)
The expression is undefined when \(x^2 + 4x - 5 = 0\)
\(x^2 + 5x - x - 5 = 0\)
\(x(x + 5) - 1(x + 5) = 0\)
\((x - 1)(x + 5) = 0\)
The expression is undefined when x = 1 or -5.
10.

Which of the following could be the inequality illustrated in the sketch graph above?

A. y≥2x+3

B. y≤-3x+3

C. y < 3x+2

D. y≤x +3

E. y≥3x+2.

Detailed Solution

Gradient of the line = \(\frac{3 - 0}{0 - 1}\)
= -3
y = -3x + b.
Using (1,0), we have
0 = -3(1) + b
0 = -3 + b
b = 3
y = -3x + 3
\(\therefore\) The graph illustrates y \(\leq\) -3x + 3.
1.

Find (101\(_2\))\(^2\), expressing the answer in base 2.

A. 10101

B. 11001

C. 10010

D. 11101

E. 10110

Detailed Solution

You can convert it to base 10 and square, then re-convert it after the operation.
OR
You can multiply it straight applying the rules of binary multiplication.
2.

If three children shares N10.50 among themselves in ratio 6:7:8, how much is the largest share?

A. N3.00

B. N3.50

C. N4.00

D. N4.50

E. N5.00

Detailed Solution

Ratio = 6 + 7 + 8 = 21
21 = N10.50
1 = 1050K/21 = 50K
6 = 6 x 50K = N3.00
7 = 7 x 50K = N3.50
8 = 8 x 50K = N4.00
the Largest share = N4.00
3.

Express 0.000834 in standard form

A. 8.34 x 10-4

B. 8.34 x 10-3

C. 8.34 x 103

D. 8.34 x 104

E. 8.34 x 106

A

4.

Given that log2a = log84, find a

A. 21/3

B. 42/3

C. 42/3

D. 22/3

E. 23

Detailed Solution

Log2a = Log84
Log2a = Log882/3 → 2/3Log88 → 2/3 x 1
Log2a = 2/3
Recall; If Logax = y ∴ ay = x
Log2a = 2/3
22/3 = a
5.

By selling some crates of soft drinks for N600.00, a dealer makes a profit of 50%. How much did the dealer pay for the drinks?

A. N1,200.00

B. N900.00

C. N450.00

D. N400.00

E. N200.00

Detailed Solution

S.P = N600.00
(100 + 50)% = N600
150% = N600
1% = \(\frac{600}{150}\)
100% = \(\frac{600}{150} \times 100%\)
= N400
6.

Find the nth term Un of the A.P., 11, 4, -3,....... .

A. Un=19+7n

B. Un=19-7n

C. Un=18+7n

D. Un= 18-7n

E. Un= 17-7n

Detailed Solution

A.P 11, 4, -3
1st term = 11
A.P = a, a + d, a + 2d ...... a + (n - 1)d
If a = 11
a + d = 4
d = 4 - 11 = -7
nth term = a + (n-1)d
         = 11 + (n-1)(-7)
         = 11 - 7n + 7
         = 18 - 7n
7.

Lf 16/9 , x, 1, y are in Geometric Progression (GP), find the product of x and y.

A. 9/16

B. 3/4

C. 1

D. 4/3

E. 16/6

Detailed Solution

16/9, x, 1, y => a, ar, ar2, ar3
ar2 = 1 => 16r2/9 = 1 => 16r2
9 => r2 = 9/16 => r = 3/4
ar2 = y = ar2 x r = 1 x 3/4 = 3/4
x xy = 4/3 x 3/4 = 1
8.

If R = [2, 4, 6, 7] and S = [1, 2, 4, 8], then R∪S equal

A. [1,2,4,6,7,8]

B. [1,2,4,7,8]

C. [1,4.7,8]

D. [2.6.7]

E. [2.4]

Detailed Solution

R = {2, 4, 6, 7}; S = {1, 2, 4, 8}
R \(\cup\) S = {1, 2, 4, 6, 7, 8}
9.

Find the value(s) of x for which the expression is undefined: \(\frac{6x - 1}{x^2 + 4x - 5}\)

A. +4 or+1

B. -5 or +1

C. -5 or -1

D. +5 or -1

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

Detailed Solution

\(\frac{6x - 1}{x^2 + 4x - 5}\)
The expression is undefined when \(x^2 + 4x - 5 = 0\)
\(x^2 + 5x - x - 5 = 0\)
\(x(x + 5) - 1(x + 5) = 0\)
\((x - 1)(x + 5) = 0\)
The expression is undefined when x = 1 or -5.
10.

Which of the following could be the inequality illustrated in the sketch graph above?

A. y≥2x+3

B. y≤-3x+3

C. y < 3x+2

D. y≤x +3

E. y≥3x+2.

Detailed Solution

Gradient of the line = \(\frac{3 - 0}{0 - 1}\)
= -3
y = -3x + b.
Using (1,0), we have
0 = -3(1) + b
0 = -3 + b
b = 3
y = -3x + 3
\(\therefore\) The graph illustrates y \(\leq\) -3x + 3.