There are 20 books on Algebra and Calculus in one library. For the greatest number of selections each of which consists of 5 books on each topic. If the possible number of Algebra books are N, then the value of N/2 is __________.

The number of n digit numbers which consists of the digit 1 and 2 only if each digit is to be used at least once is equal to 510, then n is equal to ________.

Let N be the number of quadratic equations with coefficients from {0, 1, 2, ……..,9} such that zero is a solution of each equation. Then the value of N is

There are 3 men and 7 women taking a dance class. If N ils number of different ways in which each man be paired with a women partner, and the four remaining women be paired into two pairs each of two, then the value of N//90 is_________.

There are 'n' different books and 'p' copies of each. The number of ways in which a selection can be made from them is

If the number of selections of 6 different letters that can be made from the words SUMAN and DIVYA so that each selection contains 3 letters from each word is N^2, then the value of N is________.

10 different books and 2 different pens are given to 3 boys so that each gets equal number of things. The probability that the same boy does not receive both the pens is

There are 3 books of mathematics, 4 of science, and 5 of literature. How many different collections can be made such that each collection consists of (1)one book of each subject, (2)at least one book of each subject, (3)at least one book of literature.

Find the number of ways of selecting 9 ball from 6 red balls, 5 white balls and 5 blue balls if each selection consists of 3 balls of each colour.

Find the number of ways of selecting 9 balls from 6 red balls, 5 white balls and 5 blue balls if each selection consists of 3 balls fo each colour.