A man has 7 friends. In how many ways he can invite one or more of them for a tea party

English

Gujarati

Hindi

6.Permutation and Combination

easy

A man has $7$ friends. In how many ways he can invite one or more of them for a tea party

A

$128$

B

$256$

C

$127$

D

$130$

Solution

(c) Required number of ways = ${2^7} – 1 = 127$.

{Since the case that no friend be invited i.e., $^7{C_0}$ is excluded}.

Standard 11

Mathematics

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