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.

2,791.

Simplify \(\frac{2}{a+b}-\frac{1}{a-b}\)

A.

\(\frac{3}{a+b}\)

B.

\(\frac{a-3b}{a^2-b^2}\)

C.

\(\frac{3a-b}{a^2 – b^2}\)

D.

\(\frac{a-3b}{a^2+b^2}\)

Correct answer is B

Simplify \(\frac{2}{a+b}-\frac{1}{a-b}; \frac{2(a-b)-1(a+b)}{(a+b)(a-b)}\)

= \(\frac{2a-2b-a-b}{(a+b)(a-b)}\)

= \(\frac{a-3b}{a^2 - ab + ab - b^2}\)

= \(\frac{a-3b}{a^2-b^2}\)

2,792.

A boy walks 800m in 20 minutes. Calculate his average speed in km per hour

A.

2.4

B.

4

C.

16

D.

24

Correct answer is A

\(Average \hspace{1mm}speed = \frac{Distance}{Time\hspace{1mm} taken}\\
Distance = 800m = \frac{800}{1000}km = 0.8km\\
Time\hspace{1mm}taken = 20\hspace{1mm}minutes = \frac{20}{60}hr=\frac{1}{3}hr\\Average \hspace{1mm} speed = \left(0.8\div \frac{1}{3}\right)km/hr = (0.8\times3)km/hr\\=2.4km/hr\)

2,793.

Find the range of values of x for which\(\frac{x+2}{4}-\frac{x+1}{3}>\frac{1}{2}\)

A.

x > 4

B.

x > -4

C.

x < 4

D.

x < -4

Correct answer is D

\(\frac{x+2}{4}-\frac{x+1}{3}>\frac{1}{2}\\
\frac{3(x+2)-4(x+1)>6}{12}; 3x + 6 – 4x – 4 > 6\
-x +2>6; -x > 4; x < -4\)

2,794.

The table above gives the marks scored by a group of students in a test Use the table to answer the Question below
What is the probability of selecting a student from the group that scored 2 or 3?

A.

\(\frac{1}{11}\)

B.

\(\frac{5}{22}\)

C.

\(\frac{7}{22}\)

D.

\(\frac{6}{11}\)

Correct answer is D

Prob (2 or 3) = prob(2) + prob(3)
Prob (mark 2) \(=\frac{7}{22}\) + Prob(mark 3) = \(\frac{5}{22}\)
Prob(2 or 3) \(=\frac{7}{22}+\frac{5}{22}=\frac{12}{22}=\frac{6}{11}\)

2,795.

The table above gives the marks scored by a group of students in a test Use the table to answer the Question below
What is the median mark?

A.

1

B.

2

C.

3

D.

4

Correct answer is C

Median = 0, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5
Median mark = \(\frac{3+3}{2} = \frac{6}{2} = 3\)