Question

A boy read 2/7th of a book on one day and 4/5th of the remainder on another day. if there were 12 pages unread, how many pages did the book contain

Answer 1

Hey!

Let the total number of pages be x.

First day=2/7of x = 2/7*x= 2x/7.

Remaining pages= x-2x/7 =5x/7.

Another day= 4/5 of 5x/7 = 4x/7

Remaining pages= 5x/7 - 4x/7 = x/7.

Also, Remaining pages= 12.

So, x/7=12.
x= 12*7=84pages.

The book contains 84 pages.

Hope it helps.

Answer 2

✪||Solution||✪

Let, the total pages be x

book read on 1st day = 2/7 × x

= 2x/7

book read on 2nd day = ( x - 2x/7 ) × 4/5

= ( 7x - 2x/7 ) × 4/5

= 5x/7 × 4/5

= 20x/35

= 4x/7

no. of pages unread = 12 pages

Total pages in the book = x

2x/7 + 4x/7 + 12pages = x

6x/7 + 12pages = x

12pages = x - 6x/7

12 pages = x/7

12 pages × 7 = x

84 pages = x

Total pages in a book is 84 pages.