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.

3,761.

A box contains 5 blue balls, 3 red balls and 2 white balls. Two balls are selected from the box with replacement. Find the probability of obtaining two blue or two red balls

A.

17/50

B.

3/25

C.

1/50

D.

3/250

Correct answer is A

Blue balls = 5
Red balls = 3
White balls = 2
Total = 10
P(Two blue) = 5/10 * 5/10 = 25/100
P(Two Red) = 3/10 * 3/10 = 9/100
∴P(Two blue or two red balls)
= 25/100 + 9/100
= 34/100
= 17/50

3,762.

How many possible ways are there of seating seven people P,Q,R,S,T,U and V at a circular table

A.

360

B.

720

C.

2520

D.

5040

Correct answer is B

(n - 1)! = (7 - 1)!
= 6!
= 6*5*4*3*2*1
= 720 ways

3,763.

In how many ways can 6 coloured chalks be arranged if 2 are the same colour?

A.

60

B.

120

C.

240

D.

360

Correct answer is D

\(\frac{6!}{2!}=ways=\frac{6\times5\times4\times3\times2!}{2!}\\=6\times5\times4\times3\\=360\hspace{1mm}ways\)

3,764.

Find the value of t if the standard deviation of 2t, 3t, 4t, 5t, and 6t is √2

A.

1

B.

2

C.

3

D.

4

Correct answer is A

No explanation has been provided for this answer.

3,765.

The model height and range of heights 1.35, 1.25, 1.35, 1.40, 1.35, 1.50, 1.35, 1.50, and 1.20 are m and r respectively. Find m+2r.

A.

1.35

B.

1.65

C.

1.95

D.

3.00

Correct answer is C

1.35, 1.25, 1.35, 1.40, 1.35, 1.50, 1.35, 1.50, and 1.20
Modal height = 1.35
Range (r) = 1.50 - 1.20
= 0.30
∴m + 2r = 1.35 + 2(0.30)
= 1.35 + 0.60
= 1.95