Mathematics questions and answers

Mathematics Questions and Answers

How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.

3,846.

Three consecutive terms of a geometric progression are given as n-2, n and n+3. Find the common ratio

A.

1/4

B.

1/2

C.

2/3

D.

3/2

Correct answer is D

\(r=\frac{n}{n-2}\hspace{1mm}and\hspace{1mm}r=\frac{n+3}{n}\\∴\frac{n}{n-2}=\frac{n+3}{n}\\n^2 = n^2 +3n - 2n-6\\0=n-6\\∴n=6\\But\hspace{1mm}r = \frac{n}{n-2}\\r=\frac{6}{6-2}\\\frac{6}{4}=\frac{3}{2}\)

3,847.

Find the value of x and y respectively if 3x - 5y + 5 = 0 and 4x - 7y + 8 = 0

A.

-5, -4

B.

-4,. -5

C.

4, 5

D.

5, 4

Correct answer is D

3x - 5y + 5 = 0 → eqn1
4x - 7y + 8 = 0 → eqn2
eqn1 * 4; 12x - 20y + 20 = 0 → eqn3
eqn2 * 3; 12x - 21y + 24 = 0 → eqn4
eqn3 - eqn4 = y - 4 = 0
∴ y = 4
From eqn1,
3x - 5y + 5 = 0
3x - 5(4) + 5 = 0
3x - 20 + 5 = 0
3x - 15 = 0
3x = 15
x = 5
x and y = 5, 4 respectively

3,849.

The graph of the function y = x\(^2\) + 4 and a straight line PQ are drawn to solve the equation x\(^2\) - 3x + 2 = 0. What is the equation of PQ?

A.

y = 3x - 2

B.

y = 3x + 2

C.

y = 3x - 4

D.

y = 3x + 4

Correct answer is B

x\(^2\) + 4 = x\(^2\) - 3x + 2
3x + 2 = y

3,850.

Find the range of the value of x satisfying the inequalities 5 + x \(\leq\) 8 and 13 + x \(\geq\) 7

A.

-3 \(\leq\) x \(\leq\) 3

B.

3 \(\leq\) x \(\leq\) 6

C.

-6 \(\leq\) x \(\leq\) 3

D.

-6 \(\leq\) x \(\leq\) -3

Correct answer is C

5 + x \(\leq\) 8 and 13 + x \(\geq\) 7
5 + x \(\leq\) 8
X \(\leq\) 8 – 5
X \(\leq\) 3
And 13 + x \(\geq\) 7
X \(\geq\) 7 – 15
X \(\geq\) -7
Combining the two together
-6 \(\leq\) x \(\leq\) 3