CAT 1999 — QA Question 5
Forming a committeeEasy
For a scholarship, at the most n candidates out of 2n + 1 can be selected. If the number of different ways of selection of at least one candidate is 63, the maximum number of candidates that can be selected for the scholarship is
Answer & solution
3
- B
4
- C
6
- D
5
Solution
At least 1 and at most n are to be selected
⇒ 2n+1C1 + 2n+1C2 + ... + 2n+1Cn = 63
(22n+1 - 2) = 63
⇒ n = 3
Hence, option (a).