books

A student is allowed to select at most ‘n’ books from a collection of 2n + 1 books. If the total number of ways in which a student selects atleast one book is 63 then the value of n is

#Combinatorics #MathProblem #Math

Easy Math Editor

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Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

n=3.

Biswaroop Roy - 7 years, 6 months ago

give the solutions please??

gopal chpidhary - 7 years, 6 months ago

Do you know? If yes.Then why are you asking for it? If no here you go: for selecting k books from 2n+1 books number of ways is: 2n+1 C k. Like that we can say required answer is (2n+1 C 0)+(2n+1 C 1)+.........(2n+1 C n)-1=(2^(2n+1)/2)-1=63 =>n=3.

And please try to post better problems.

Biswaroop Roy - 7 years, 6 months ago

n=3

Anirudha Nayak - 7 years, 6 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$