Question

10. In a library 20% books are in hindi, 50% of the remaining are in english and the remaining 9000 are in various other languages. What is the total number of books in english

Answer 1

$\textbf{\huge{ANSWER:}}$

$\sf{Given:}$

20% of the books➡️ Hindi

50% of the remaining books➡️ English

Still Remaining Books➡️ 9000

$\sf{To\:find:}$

The total number of English books

$\sf{Your\:Solution:}$

Let the total number of books be = x

The books in Hindi = 20% of x

=》 $\frac{20x}{100}$

=》 $\frac{x}{5}$

Remaining = x - $\frac{x}{5}$

=》 $\frac{4x}{5}$

50% of the remaining = 50% of $\frac{4x}{5}$

=》 $\frac{50}{100}\times\frac{4x}{5}$

=》 $\frac{2x}{5}$ = English Books

According to your question :-

x = $\frac{x}{5} + \frac{2x}{5} + 9000$

=》 x = $\frac{x + 2x + 45000}{5}$

=》 x = $\frac{3x + 45000}{5}$

=》 5x = 3x + 45000

=》 5x - 3x = 45000

=》 2x = 45000

=》 x = $\frac{45000}{2}$

=》 $\tt{x = 2250}$

Now, we've got the value of x, that means, we've got the total number of books. So, we can easily find out the number of the English Books.

English books = $\frac{2x}{5}$

=》 x = 2250

=》 $\frac{2}{5}\times2250$

=》 $\boxed{\tt{900}}$