Ramesh has 6 friends. In how many ways can he invite one or more of them at a dinner?

Options

A. 61
B. 62
C. 63
D. 64

Answer

C

Explanation

He can invite one, two three, four, five or six friends at the dinner. So total number of ways of his invitation

= `""^(6)C_(1) + ""^(6)C_(2) + ""^(6)C_(4) + ""^(6)C_(5) + ""^(6)C_(6)`
`=2^(6) - 1 = 63`
Ans.[3]