Waste less time on Facebook — follow Brilliant.
×

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

Note by Gopal Chpidhary
4 years, 1 month ago

No vote yet
5 votes

  Easy Math Editor

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold

- bulleted
- list

  • bulleted
  • list

1. numbered
2. list

  1. numbered
  2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1

paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
    # 4 spaces, and now they show
    # up as a code block.

    print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears 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} \( \boxed{123} \)

Comments

Sort by:

Top Newest

n=3.

Biswaroop Roy - 4 years, 1 month ago

Log in to reply

n=3

Anirudha Nayak - 4 years, 1 month ago

Log in to reply

give the solutions please??

Gopal Chpidhary - 4 years, 1 month ago

Log in to reply

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 - 4 years, 1 month ago

Log in to reply

×

Problem Loading...

Note Loading...

Set Loading...