A box contains 4 red, 3 white and 2 blue balls. Three balls are drawn at random. Find out the number of ways of selecting the balls of different colours?

62

48

12

24

Correct Answer : D

The 288^{th} term of the series a, b, b, c, c, c, d, d, d, d, e, e, e, e, e, f, f, f, f, f, f…. is

The infinite sum 1?+4 / 7+?9 / 7^{2}+?16 / 7^{3} ? 25 / 7^{4} ? .... equals

What is the sum of all two-digit numbers that give a remainder of 3 when they are divided by 7