Risa was attempting to read a book within a week. On Monday, she had read
37 of the book. By Friday, she had read another 261 pages and the ratio of the number of pages read to the total number of pages was 8 : 9. Find the average number of pages Risa should have read each day to complete the book in a week.
|
Read |
Unread |
Total |
Monday |
3x9 = 27 u |
4x9 = 36 u |
7x9 = 63 u |
Change |
+ 261 |
- 261 |
|
Friday |
8x7 = 56 u |
1x7 = 7 u |
9x7 = 63 u |
Number of pages that Risa read
= 56 u - 27 u
= 29 u
29 u = 261
1 u = 261 ÷ 29 = 9
Total number of pages
= 63 u
= 63 x 9
= 567
Average number of pages to read per day
= 567 ÷ 7
= 81
Answer(s): 81