Joelle flipped her book to the middle. The sum of the two facing page numbers is 285.
- 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 = 285
2 u = 285 - 1
2 u = 284
1 u = 284 ÷ 2 = 142
Smaller page number
= 1 u
= 142
Bigger page number
= 1 u + 1
= 142 + 1
= 143
The two page numbers are 142 and 143.
(b)
Since Joelle 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
= 142 + 142
= 284
Answer(s): (a) 142, 143; (b) 284