Mathematics Past Questions and Answers

Marks scored by some children in an arithmetic test are:5, 3, 6, 9, 4, 7, 8, 6, 2, 7, 8, 4, 5, 2, 1, 0, 6, 9, 0, 8.
The arithmetic mean of the marks is

A 6
B 5
C 8
D 7
E 10

Question 12:

The weights of 30 new-born babies are given as follow: 6, 9, 5, 7, 6, 7, 5, 8, 9, 5, 7, 5, 8, 7, 8, 7, 5, 6, 5, 7, 6, 9, 9, 7, 8, 8, 7, 8, 9, 8. The mode is

A 6
B 5
C 8
D 7
E 10

Question 13:

If $\sin x° = \frac{a}{b}$, what is $\sin (90 - x)°$?

A $\frac{\sqrt{b^2 - a^2}}{b}$
B 1$\frac{-a}{b}$
C $\frac{b^2 - a^2}{b}$
D $\frac{a^2 - b^2}{b}$
E $\sqrt{b^2 - a^3}$

Question 14:

7 pupils of average age 12 years leave a class of 25 pupils of average age 14 years. If 6 new pupils of average age 11years join the class, what is the average age of the pupils now in the class?

A 13years
B 12 years 7$\frac{1}{2}$ months
C 13 years 5 months
D 13 years 10 months
E 11 years

Question 15:

A sum of money invested at 5% per annum simple interest amounts to $285.20 after 3 years. How long will it take the same sum to amount to $434.00 at 7$\frac{1}{2}$% per annum simple interest?

A 7$\frac{1}{2}$ years
B 10 years
C 5 years
D 12 years
E 14 years