CREST Mental Maths Olympiad Class 10 Previous Year Papers

Q.1

Find the value of question mark (?).
65% of 240 + ? % of 150 = 210

Q.2

The average age of three children and their father is 17 years. The average age of these children and their mother is 13 years. Mother's age is 22 years, what is the father's age?

Q.3

A man can row upstream at 12 km/h and downstream at 16 km/h. Find the man's speed in still water.

Q.4

Angles of elevation of top and bottom of a flag kept on a flag post at 30 m distance are 45^o and 30^o respectively. What is the height of the flag?

Q.5

In the figure, find ∠AOC if ∠AOB = 68^o and ∠BOC = 42^o.

Q.6

Find the simple interest on $1200 for 5 years at 6% per annum.

Q.7

A person covers a certain distance at a speed of 60 km/h and returns to the starting point at a speed of 40 km/h. Find the average speed of the person for the whole journey.

Q.8

Factorise:
6x² - 5xy - 6y²

Q.9

What is the mean of first 12 prime numbers?

Q.10

Express 4/(√5 - 1) with a rational denominator.