A, B and C run a race of 100 meters. When A finishes the race, B is 10 meters behind. When B finishes the race C is 10 meters behind. How far was C behind A when the latter finishes the race?
The ratio of boys to girls in a school is 11 : 9. If the number of boys is decreased by 25 and the number of girls is increased by 25, the new ratio becomes 1 : 1. Find the total number of students in the school.
Find the odd number in the series:
0, 2, 6, 12, 20, 30, 40, 56