If there are 20 steamers plying between places A and B, in how many ways could the round trip from A be made if the return was made on : a different steamer ?

If there are 20 steamers plying between places A and B, in how many ways could the round trip from A be made if the return was made on : the same steamer ?

How many selections of 4 books can be made from 8 different-books ?

There are 5 routes from place A to place B and 3 routes from place B to place C. Find how many different routes are there from A to C via B.

How many signals can be made by hoisting 5 flags of different colours ?

From 4 mangoes, 5 oranges and 6 apples, how many selections of fruits can be made by taking at least one of them ?

From 2 mangoes, 3 oranges and 4 apples, how many selections of fruits can be made by taking : at least one of each kind ?

From 2 mangoes, 3 oranges and 4 apples, how many selections of fruits can be made by taking : at least one of them?

Distance between Place A and Place B is (4x-3)km . A bus started from A and covered (3x+1)km in 1 hour. How much distance is still left to cover?

In an electric field the work done in bringing a 2 coulomb charge from infinity to a point a is 10 joules and in bringing the same charge to some another point B is 20 joule find the potential difference between two points A and B what would be the work done if the same charge is brought directly from A to B.