A father with 8 children takes three at a time to the Zoo as often as he can without taking the same three children together more than once. How often will he go?

There are three prizes to be distributed among 6 students. In how many ways can this be done when no boy gets more than one prize.

Sarita and Ameena decide to paly a game of expressions. They take the variable x and the number 3 and see how many expressions they can make. The condition is that they should use not more than one out of the four number operations and every expression must have x in it. Can you help them? Sarita thinks of (x + 3) Then Ameena comes up with (x - 3) Is (3x+5) allowed? Is (3x + 3) allowed?

There is a circular path around a sports field. Sonia takes 18 minutes to drive one round of the field, while Ravi takes 12 minutes for the same. Suppose they both start at the same point and at the same time, and go in the same direction. After how many minutes will they meet again at the starting point ?

Sohan has x children by his first wife. Geeta has (x+1) children by her first husband. The marry and have children of their own. The whole family has 24 children. Assuming that two children of the same parents do not fight, prove that the maximum possible number of fights that can take place is 191.

A class has 30 students, In how many ways can three prizes be awarded so that: no student gets more than one prize?

An express train takes 1 hour less than a passenger train to travel 132 km between Mysore and Bangalore (without taking into consideration the time they stop at intermediate stations). If the average speed of the express train is 11 km/hr more than that of the passenger train, find the average speed of the two trains.

A carpenter was hired to build 192 window frames. The first day he made five frames and each day, thereafter he made two more frames than he made the day before. How many days did it take him to finish the job?

Deepak takes 6 days less than the time taken by Suresh to finish a piece of work. If both Deepak and Suresh together can finish it in 4 days, find the time taken by Suresh to finish the work.