Let the total no. of pages in the book be

(4/9)th of a book is read on first day.

So no. of pages read on this day

And no. of pages remaining

(3/5)th part of the remaining is read on next day.

No. of pages read on this day

And no. of pages remaining unread

These remaining pages are those 100 pages of the book which were left unread.

Hence the book contains a total of 150 pages.

Verified answer

Answer:

☆Let the number of pages the book contained be x.

♧Part read in 1st day=4x/9

♤Remainder=x-4x/9=9x/9 - 4x/9=5x/9

♡Part read in next day=5x/9 × 3x/5=x/3

◇Remainder=x-x/3=3x/3-x/3=2x/3

ACQ,

》》2x/3=100

》》x=100×3/2=50×3=150 pages