JAMB Mathematics Past Questions & Answers - Page 298

1,486.

Solve the simultaneous equations \(\frac{2}{x} - {\frac{3}{y}}\) = 2, \(\frac{4}{x} + {\frac{3}{y}}\) = 10

A.

x = \(\frac{3}{2}\), y = \(\frac{3}{2}\)

B.

x = \(\frac{1}{2}\), y = \(\frac{3}{2}\)

C.

x = \(\frac{-1}{2}\), y = \(\frac{-3}{2}\)

D.

x = \(\frac{1}{3}\), y = \(\frac{3}{2}\)

Correct answer is B

\(\frac{2}{x} - {\frac{3}{y}}\) = 2.....(1)

\(\frac{4}{x} + {\frac{3}{y}}\) = 10 ... (2)

(1) + (2):

\(\frac{6}{x}\) = 12 \(\to\) x = \(\frac{6}{12}\)

x = \(\frac{1}{2}\)

put x = \(\frac{1}{2}\) in equation (i)

= 4 - \(\frac{3}{y}\) = 2

= 4 - 2

= \(\frac{3}{y}\)

therefore y = \(\frac{3}{2}\)

1,487.

If the function f(fx) = x3 + 2x2 + qx - 6 is divisible by x + 1, find q

A.

-5

B.

-2

C.

2

D.

5

Correct answer is A

x + 1 = 0, x = -1; f(x) = x3 + 2x2 + qx - 6

0 = -1 + 2 - q - 6

q = -5

1,488.

A survey of 100 students in an institution shows that 80 students speak Hausa and 20 students speak Igbo, while only 9 students speak both language. How many students speak neither Hausa nor Igbo?

A.

0

B.

9

C.

11

D.

20

Correct answer is B

Let the number of students that speak Hausa and Igbo be represented by H and I respectively.

n(H only) = 80 - 9 = 71.

n(I only) = 20 - 9 = 11.

n(neither H nor I) = 100 - (71 + 9 + 11)

= 100 - 91 = 9 students.

1,489.

If U = (s, p, i, e, n, d, o, u, r), X = (s, p, e, n, d) Y = (s, e, n, o, u), Z = (p, n, o, u, r) find X ∩( Y ∪ Z)

A.

(p, o, u, r)

B.

(s, p, d, r)

C.

(s, p, n, e)

D.

(n, d, u)

Correct answer is C

\(Y \cup Z\) = \({s, e, n, o, u, p, r}\)

\(X \cap (Y \cup Z)\) = \({p, e, n}\)

1,490.

Find the simple interest rate percent per annum at which N1,000 accumulates to N1,240 in 3 years

A.

6%

B.

8%

C.

10%

D.

12%

Correct answer is B

1 = \(\frac{PRT}{100}\)

1 = 1240 - 1000

= 240

R = \(\frac{240 \times 100}{100 \times 3}\)%

= 8%