Betty was attempting to read a book within a week. On Monday, she had read
27 of the book. By Friday, she had read another 287 pages and the ratio of the number of pages read to the total number of pages was 9 : 11. Find the average number of pages Betty should have read each day to complete the book in a week.
|
Read |
Unread |
Total |
Monday |
2x11 = 22 u |
5x11 = 55 u |
7x11 = 77 u |
Change |
+ 287 |
- 287 |
|
Friday |
9x7 = 63 u |
2x7 = 14 u |
11x7 = 77 u |
Number of pages that Betty read
= 63 u - 22 u
= 41 u
41 u = 287
1 u = 287 ÷ 41 = 7
Total number of pages
= 77 u
= 77 x 7
= 539
Average number of pages to read per day
= 539 ÷ 7
= 77
Answer(s): 77