It takes 24 hours for 10 men to make 15 cakes. How many cakes can be made if 8 men work for 36 hours?
The ratio of present age of father, mother and son is 7:5:3. The sum of their ages is 75. What is the present age of the son in years?
How many prime numbers are there between 1 to 11?
What is the smallest positive integer that is evenly disvible by both 21 and 9?