WAEC Past Questions and Answers - Page 2997

14,981.

If a positive integer, list the values of x which satisfy the equation 3x - 4 < 6 and x - 1 > 0

A.

{1, 2, 3}

B.

{2, 3}

C.

{2, 3, 4}

D.

{2, 3, 4, 5}

Correct answer is B

3x - 4 < 6 = 3x < 6 = 4

3x < 10

x < \(\frac{10}{3}\)

x < 3.33 and x - 1 = 0

n > 1 = 1< x; since x is an integer, and 1 < x3.33

x = {2, 3}

14,982.

solve \(\frac{2x + 1}{6} - \frac{3x - 1}{4}\) = 0

A.

1

B.

\(\frac{1}{5}\)

C.

-\(\frac{1}{5}\)

D.

-1

Correct answer is A

\(\frac{2x + 1}{6} - \frac{3x - 1}{4}\) = 0

\(\frac{4(2n + 1) - 6(3x - 1)}{24}\) = 0

-10x + 10 = 0

-10x = -10

x = \(\frac{-10}{-10}\)

x = 1

14,983.

An arc of a circle subtends an angle of 60o at the centre. If the radius of the circle is 3cm, find , in terms of \(\pi\), the length of the arc

A.

\(\pi\)cm

B.

2\(\pi\)cm

C.

3\(\pi\)cm

D.

6\(\pi\)cm

Correct answer is A

Length of arc = \(\frac{\theta}{360} \times 2\pi r\)

= \(\frac{60}{360} \times 2\pi \times 3cm\)

= \(\pi\)cm

14,984.

The capacity of a water tank is 1,800 litres. If the tank is in form of a cuboid with base 600cm by 150 cm. Find the height of the tank

A.

2cm

B.

20cm

C.

200cm

D.

2000cm

Correct answer is B

1 litre = 1000cm3

1800 litre = 1800 x 1000cm3

l x b x h = capacity

600 x 150 x h = 1800000

h = \(\frac{1800000}{600 \times 150}\)cm

h = 20cm

14,985.

If 85% of x is N3230, what is the value of x?

A.

N2745.50

B.

N3714.50

C.

N3800.00

D.

N4845.00

Correct answer is C

85% of x = 3230

\(\frac{85}{100} \times x\) = N3230

x = \(\frac{100}{85}\) x N3230

x = N3800.00