JAMB Mathematics Past Questions & Answers

1,536.

If x = \(\begin{pmatrix} 1 & 0 & 1 \\ 2 & -1 & 0 \\ -1 & 0 & 1\end{pmatrix}\) and y = \(\begin{pmatrix} -1 & 1 & 2 \\ 0 & -1 & -1 \\ 2 & -1 & 1\end{pmatrix}\)
find 2x - y

\(\begin{pmatrix} 3 & -1 & 0 \\ 4 & -3 & -1 \\ -4 & 1 & 1\end{pmatrix}\)

\(\begin{pmatrix} 3 & -1 & 0 \\ 4 & -1 & 1 \\ -4 & 1 & 1\end{pmatrix}\)

\(\begin{pmatrix} 3 & -1 & 0 \\ 4 & -3 & 1 \\ -4 & 1 & 1\end{pmatrix}\)

\(\begin{pmatrix} 3 & -1 & 0 \\ 4 & 1 & 1 \\ -4 & -1 & 1\end{pmatrix}\)

View answer & explanation

Correct answer is B

2(1) - (-1) = 3 2(2) - (0) = 4 2(-1) - (2) = -4

2(0) - (1) = -1 2(-1) - (-1) = -1 2(0) - (-1) = 1

2(1) - 2 = 0 2(0) - (-1) = 1 2(1) - (1) = 1

\(\begin{pmatrix} 3 & -1 & 0 \\ 4 & -1 & 1 \\ -4 & 1 & 1\end{pmatrix}\)

1,537.

Find p, q for which \(\begin{pmatrix} 2p & 8 \\ 3 & -5q \end{pmatrix}\)\(\begin{pmatrix} 1 \\ 2\end{pmatrix}\) = \(\begin{pmatrix}24 \\ -17\end{pmatrix}\)

-4

4,2

View answer & explanation

Correct answer is C

2p x 1 + 8 x 2 = 24

\(\to\) 4p = 24 - 8 = 16,

p = 4

3 x 1 + -5q x 2 = -17

\(\to\) -10q = -17 - 3

-10q = -20

q = 2

1,538.

The sum of the ages of Musa and Lawal is 28 years. After sharing a certain sum of money in the ratio of their ages, Musa gets N600 and Lawal N800. How old is Lawal?

14 years

20 years

12 years

16 years

View answer & explanation

Correct answer is D

M + L = 28,

M : L = 600 : 800

= 3 : 4

\(\frac{M}{L}\) = \(\frac{3}{4}\) \(\to\) M = \(\frac{3}{4}\)L

\(\frac{3}{4}\)L + L = 28

\(\frac{7L}{4}\) = 28

L = \(\frac{4 \times 28}{7}\)

= 16