A person wishes to make up as many different parties as he can out of his 16 friends such that each party consists of the same number of persons. How many friends should be invite ?

A person tries to form as many different parties as he can, out of his 20 friends. Each party should consist of the same number. How many friends should be invited at a time? In how many of these parties would the same friends be found?

A man has 6 friends. In how many ways can he invite one or more of his friends to a party ?

In how many ways can a person invite one or more of his 8 friends to a feast ?

A man has 6 friends. Number of ways he can invite one or more of them to a tea party is

How many different 4-digit numbers can he formed from the digits 2, 3, 4 and 6 if each digit is used only once in a number ? Further, how many of these numbers : end in a 4 ?

How many different 4-digit numbers can he formed from the digits 2, 3, 4 and 6 if each digit is used only once in a number ? Further, how many of these numbers : end in a 3 ?

There are three books of physics, four of chemistry and five of mathematics. How many different collections can be made such that each collection consists of (i) one book of each subject (ii) atleast one book of each subject. (iii) atleast one book of mathematics.

How many different 4-digit numbers can he formed from the digits 2, 3, 4 and 6 if each digit is used only once in a number ? Further, how many of these numbers : end in a 3 or 6 ?

Champa went to a ‘Sale' to purchase some pants and skirts, When her friends asked her how many of each she had bought, she answered. "The number of skirts is two less than twice the number of pants purchased. Also, the number of skirts is four less than four times the number of pants purchased". Help her friends to find how many pants and skirts Champa bought.

A man has 10 friends. In how many ways he can invite one or more of them to a party?