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.

2,121.

The numbers 3, 2, 8, 5, 7, 12, 9 and 14 are the marks scored by a group of students in a class test. If P is scored by an group of students in a class test. If P is the mean and Q the median, the P + Q is

A.

18

B.

17\(\frac{1}{2}\)

C.

16

D.

15

Correct answer is D

Re-arranging them 2, 3, 5, 7, 8, 9, 12, 14

Mean = P and median = Q

P = \(\frac{2 + 2 + 5 + 7 + 8 + 9 + 12 + 14}{8}\)

\(\frac{60}{8}\) = 7.5

median (Q) = \(\frac{7 + 8}{2}\)

\(\frac{15}{2}\) = 7.5

P + Q = 7.5 + 7.5 = 15

2,122.

The goals scored by 40 football teams from three league divisions are recorded below
\(\begin{array}{c|c} \text{Number of goals} & 0 & 1 & 2 & 3 & 4 & 5 & 6 \\ \hline frequency & 4 & 3 & 15 & 16 & 1 & 0 & 1\end{array}\)
What is the total number of goals scored by all the terms?

A.

21

B.

40

C.

91

D.

96

Correct answer is C

Let x rep. number of goals
\(\begin{array}{c|c} "f & " & frequency\\\hline x & f & fx\\ 0 & 4 & 0\\1 & 3 & 3\\2 & 15 & 30\\3 & 16 & 48\\4 & 1 & 4\\5 & 0 & 0 \\ 6 & 1 & 6\end{array}\)

\(\sum fx\) = 91

Total number of goals scored is \(\sum fx\)= 91

2,123.

Taking the period of day light on a certain day to be from 5.30a.m to 7.00p.m. Calculate the angle of a pie chart designed to show the periods of the day light and of darkness on that day

A.

187o30'

B.

172o30'

C.

135o225o

D.

202o30' 157o 30'

Correct answer is D

Period of day light is from 5.30 to 7.00p.m - 13hrs 30min. interval

24hrs make 1 day

∴ period of darkness = 24hrs - 13hrs 30mins = 10hrs 30mins.

Angle of sector of daylight = \(\frac{13 \times 60 + 30 \times 360}{(24 \times 60)}\)

= \(\frac{810}{1440}\) x 360o

= \(\frac{291600}{1440}\)

= 202.5o

202.5o = 202.30o

darkness period = 360o - 202o 30'

= 157o30'

= 202o30' 157o 30'

2,124.

What is the locus of the mid-points of all chords of length 6cm within a circle of radius 5cm and with centre 0

A.

A circle of radius 4 cm and with centre O

B.

The perpendicular bisector of the chords

C.

A straight line passing through centre O

D.

A circle of radius 6 cm and with centre O

Correct answer is A

The locus of the mid-point of all chords of length 6cm within a circle of radius 5cm and with centre O is the perpendicular bisectors of the chords.

2,125.

The base of a pyramid is a square of side 8cm. If its vertex is directly above the centre, find the height, given that the edge is 4\(\sqrt3\)cm

A.

6cm

B.

5cm

C.

4cm

D.

3cm

Correct answer is C

Base of pyramid of a square of side 8cm vertex directly above the centre edge = \(4\sqrt{3}\)cm

From the diagram, the diagonal of one base is AC2 = 82 + 82

Ac2 = 64 + 64 = 128

AC = \(8\sqrt{2}\)

but OC = \(\frac{1}{2}\)AC = 8\(\sqrt{\frac{2}{2}}\) = \(4\sqrt{2}\)cm

OE = h = height

h2 = (\(4\sqrt{3}\))2

16 x 2 - 16 x 2

48 - 32 = 16

h = \(\sqrt{16}\)

= 4