On Wednesday, Zane read ³₅ of a non-fiction book. On Thursday, he read 50 pages of the non-fiction book. On Friday, he read ⁵₈ of the remaining book leaving 33 pages unread.

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

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

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

3 u = 33

1 u = 33 ÷ 3 = 11

Number of pages that Zane read on Friday
= 5 u
= 5 x 11
= 55

(b) 
Working backwards.

Number of pages unread after reading on Thursday
= 8 u
= 8 x 11
= 88

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

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

2 p = 50 + 88
2 p = 138

1 p = 138 ÷ 2 = 69

Total number of pages in the non-fiction book
= 5 p
= 5 x 69
= 345

Answer(s): (a) 55; (b) 345