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.

1,126.

The amount A to which a principal P amounts at r% compound interest for n years is given by the formula A = P(1 + (r ÷ 100)\(^n\). Find A, if P = 126, r = 4 and n = 2.

A.

N132.50K

B.

N136.30K

C.

N125.40K

D.

N257.42K

Correct answer is B

\( A = P \left(1 + \frac{r}{100}\right)^n \)

Where P = 126, r = 4,n = 2

A=126 \( \left(1 + \frac{4}{100}\right)^2 \text{Using LCM} \)

=126 \( \left(\frac{100+4}{100}\right)^2 = 126 \left(\frac{104}{100}\right)^2 \)


=126 \( \left(1.04^2 \right) \)

= 126 * 1.04 * 1.04

=136.28

A = 136.30 (approx.)

The Amount A, = N136.30k

1,127.

Find the equation of a line which is form origin and passes through the point (−3, −4)

A.

y = \( \frac{3x}{4} \)

B.

y = \( \frac{4x}{3} \)

C.

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

D.

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

Correct answer is B

The slope of the line from (0, 0) passing through (-3, -4) = \(\frac{-4 - 0}{-3 - 0}\)

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

Equation of a line is given as \(y = mx + b\), where m = slope and b = intercept.

To get the value of b, we use a point on the line, say (0, 0).

\(y = \frac{4}{3} x + b\)

\(0 = \frac{4}{3}(0) + b\)

\(b = 0\)

The equation of the line is \(y = \frac{4}{3} x\)

1,128.

The first and last term of a linear sequence (AP) are 6 and 10 respectively. If the sum of the sequence is 40. Find the number of terms

A.

nth = 3

B.

nth = 4

C.

nth = 5

D.

nth = 6

Correct answer is C

nth term of a linear sequence (AP) = a+(n − 1)d

first term = 6, last term = 10 sum − 40

i.e. a = 6, l = 10, S = 40

S\(_{n}\)= n/2(2a + (n − 1)d or Sn = ÷2 (a + l)

S\(_{n}\) = n/2(a + l)

40 = n/2(6 + 10)

40 = 8n

8n = 40

8n = 40

n = 40/8

= 5

The number of terms = 5

1,129.

Solve the equation \( 3x^2 − 4x − 5 = 0 \)

A.

x = 1.75 or − 0.15

B.

x = 2.12 or − 0.79

C.

x = 1.5 or − 0.34

D.

x = 2.35 or −1.23

Correct answer is B

Using the quadratic formula, we have

\(x = \frac{-b \pm \sqrt{b^{2} - 4ac}}{2a}\)

From the equation \(3x^{2} - 4x - 5 = 0\), a = 3, b = -4 and c = -5.

\(\therefore x = \frac{-(-4) \pm \sqrt{(-4)^{2} - 4(3)(-5)}}{2(3)}\)

= \(\frac{4 \pm \sqrt{16 + 60}}{6}\)

= \(\frac{4 \pm \sqrt{76}}{6}\)

= \(\frac{4 \pm 8.72}{6}\)

= \(\frac{4 + 8.72}{6} \text{ or } \frac{4 - 8.72}{6}\)

= \(\frac{12.72}{6} \text{ or } \frac{-4.72}{6}\)

\(x = \text{2.12 or -0.79}\)

1,130.

A man with an annual salary of N2000, has allowances of N600. If Income Tax is 5%. How much income tax expenses does he pay each year?

A.

15

B.

50

C.

70

D.

25

Correct answer is C

His annual salary = N2000 His allowances = N600 So his taxable income = Annual salary − allowance = N2000 − N600 = N1400 He pay at 5% Then, his allowance income tax 5/100 × 1400 = N70