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.

2,116.

Four boys and ten girls can cut a field in 5 hours if the boys work at \(\frac{5}{4}\) the rate at which the girls work. How many boys will be needed to cut the field in 3 hours?

A.

180

B.

60

C.

25

D.

20

Correct answer is D

Let x represents number of boys that can work at \(\frac{5}{4}\) the rate at which the 10 girls work

For 1hr. x boys will work for \(\frac{\frac{1}{5}}{4}\) x 10

x = \(\frac{4}{5}\) x 10 = 8 boys

8 boys will do the work of ten girls at the same rate 4 + 8 = 12 boys cut the field in 5 hrs

For 3 hrs, \(\frac{12 \times 5}{3}\) boys will be needed = 20 boys

2,117.

By selling 20 oranges for N1.35 a trader makes a profit of 8%. What is his percentage gain or loss if he sells the same 20 oranges for N1.10?

A.

8%

B.

10%

C.

12%

D.

15%

Correct answer is C

profit 8% of N1.35 = \(\frac{8}{100}\) x N1.35 = N0.08

Cost price = N1.35 - N0.10 = N1.25

If he sells the 20 oranges for N1.10 now

%loss = \(\frac{\text{actual loss}}{\text{Cost price}}\) x 100

\(\frac{125 - 1.10}{1.25}\) x 100

= \(\frac{0.15 \times 100}{1.25}\)

= \(\frac{15}{1.25}\)

= 12%

2,118.

A man invests a sum of money at 4% per annum simple invest. After 3 years, the principal amounts to N7,000.00. Find the sum invested

A.

N7,840

B.

N6,250.00

C.

N616.00

D.

N5,833.33

Correct answer is B

I = \(\frac{PRT}{100}\)

100(A - P) = prt

P = \(\frac{100A}{100 + RT}\)

= \(\frac{100 \times 7000}{100 + (4 \times 3)}\)

p = \(\frac{700,000}{112}\)

= N6,250.00

2,119.

Two brothers invested a total of N5,000.00 on a farm project, the farm yield was sold for N 15,000.00 at the end of the season. If the profit was shared in the ratio 2 : 3, what is the difference in the amount to profit received by the brothers?

A.

N2,000.00

B.

N4,000.00

C.

N6,000.00

D.

N10,000.00

Correct answer is A

Total amount invested by A and B = N5,000

farm yield was sold for N15,000.00

profit = 15,000.00 - 5,000.00

= N10,000.00

Profit was shared in ratio 2 : 3

2 + 3 = 5

A received \(\frac{2}{5}\) of profit = \(\frac{2}{5}\) x 10,000 = N4,000.00

A receive \(\frac{3}{5}\) of profit = \(\frac{3}{5}\) x 10,000 = N6,000.00

Difference in profit received = N6,0000 - N4,000.00

= N2,000.00

2,120.

If the length of a square is increased by 20% while while its width is decreased by 20% to form a rectangle, what is the ratio of the area of the rectangle to the area of the square?

A.

6 : 5

B.

25 : 24

C.

5 : 6

D.

24 : 25

Correct answer is D

Length and width of a square is 100%

Length increased by 20% and

Width decreased by 20% to form a rectangle

Length of rectangle = 120% to form a rectangle

Length of rectangle = 120% and

Width of rectangle = 80%

Area of rectangle = L x W

Area of square = W

Ratio of the area of the rectangle to the area of the square

A = \(\frac{\text{Area of rectangle}}{\text{Area of square}}\)

\(\frac{120 \times 30}{100 \times 100}\) = \(\frac{96}{100}\)

= 24 : 25