WAEC Past Questions and Answers - Page 3898

19,486.

Given that P = {b, d, e, f} and Q = {a, c, f, g} are subsets of the universal set U = {a,b, c, d, e, f, g}. Find P' ∩ Q

A.

{a,c}

B.

{a, c, d, g}

C.

{c, d, g}

D.

{a, c, g}

Correct answer is D

U = {a, b, c, d, e, f, g} P = {b, d, e, f} Q = {a, c, f, g} P' = {a, c, g} P' ∩ Q = {a, c, g}

19,487.

The variance of a given distribution is 25. What is the standard deviation?

A.

125

B.

75

C.

25

D.

5

Correct answer is D

S.D = \(\sqrt{Variance}\)

= \(\sqrt{25}\)

= 5

19,488.

Simplify \(5\frac{1}{4}\div \left(1\frac{2}{3}- \frac{1}{2}\right)\)

A.

\(1\frac{3}{4}\)

B.

\(3\frac{1}{2}\)

C.

\(4\frac{1}{2}\)

D.

\(8\frac{1}{2}\)

Correct answer is C

\(5\frac{1}{4}\div \left(1\frac{2}{3}- \frac{1}{2}\right)\\
\frac{21}{4}\div \left(1\frac{4-3}{6}\right)\\
\frac{21}{4}\div \left(1\frac{1}{6}\right)\\
\frac{21}{4} \times \frac{6}{7}= 4\frac{1}{2}\)

19,489.

In the diagram above, ∠PQU=36°, ∠QRT = 29°, PQ||RT. Find ∠PQR

A.

94o

B.

65o

C.

61o

D.

54o

Correct answer is B

< UQR = 29° (alternate angles)

< PQR = < PQU + < UQR

= 36° + 29°

= 65°

19,490.

PQRS is a trapezium in which |PS| = 9cm, |QR| = 15cm, |PQ| = \(2\sqrt{3}, \angle PQR = 90^o and \angle QRS = 30^o\). Calculate the area of the trapezium

A.

\(24\sqrt{3} cm^2\)

B.

\(36\sqrt{3} cm^2\)

C.

\(42\sqrt{3} cm^2\)

D.

\(72\sqrt{3} cm^2\)

Correct answer is A

No explanation has been provided for this answer.