Zoe flipped her book to the middle. The sum of the two facing page numbers is 217.
- What are the two page numbers? Give your answer in this format. (Eg 1, 2)
- How many pages are there in the book?
(a)
Smaller page number = 1 u
Bigger page number = 1 u + 1
Sum of the two facing page numbers
= 1 u + 1 u + 1
= 2 u + 1
2 u + 1 = 217
2 u = 217 - 1
2 u = 216
1 u = 216 ÷ 2 = 108
Smaller page number
= 1 u
= 108
Bigger page number
= 1 u + 1
= 108 + 1
= 109
The two page numbers are 108 and 109.
(b)
Since Zoe flipped her book to the middle, the number of pages on the left side and the right side of the book is the same.
Total number of pages in the book
= 108 + 108
= 216
Answer(s): (a) 108, 109; (b) 216
