On Thursday, Xavier read ³₅ of a non-fiction book. On Friday, he read 50 pages of the non-fiction book. On Saturday, he read ³₈ of the remaining book leaving 50 pages unread.

1. Find the number of pages read on Saturday.
2. Find the total number of pages in the non-fiction book.

(a)
Number of remaining unread pages after reading on Friday = 8 u

Number of remaining unread pages after reading on Saturday
= 8 u - 3 u
= 5 u

5 u = 50

1 u = 50 ÷ 5 = 10

Number of pages that Xavier read on Saturday
= 3 u
= 3 x 10
= 30

(b) 
Working backwards.

Number of pages unread after reading on Friday
= 8 u
= 8 x 10
= 80

Total number of pages in the non-fiction book = 5 p

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

2 p = 50 + 80
2 p = 130

1 p = 130 ÷ 2 = 65

Total number of pages in the non-fiction book
= 5 p
= 5 x 65
= 325

Answer(s): (a) 30; (b) 325