On Tuesday, Oscar read ³₅ of a story book. On Wednesday, he read 45 pages of the story book. On Thursday, he read ³₇ of the remaining book leaving 68 pages unread.

1. Find the number of pages read on Thursday.
2. Find the total number of pages in the story book.

(a)
Number of remaining unread pages after reading on Wednesday = 7 u

Number of remaining unread pages after reading on Thursday
= 7 u - 3 u
= 4 u

4 u = 68

1 u = 68 ÷ 4 = 17

Number of pages that Oscar read on Thursday
= 3 u
= 3 x 17
= 51

(b) 
Working backwards.

Number of pages unread after reading on Wednesday
= 7 u
= 7 x 17
= 119

Total number of pages in the story book = 5 p

Number of pages unread after reading on Tuesday 
= 5 p - 3 p
= 2 p

2 p = 45 + 119
2 p = 164

1 p = 164 ÷ 2 = 82

Total number of pages in the story book
= 5 p
= 5 x 82
= 410

Answer(s): (a) 51; (b) 410