The average number of pages Raeann read in a certain number of days was 13. In the next three days, Raeann read another 87 pages. As a result, the average number of pages she read increased to 17. How many days did Raeann read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 3 |
| Value |
13 |
17 |
| Number x value |
13 u |
17 u + 51 |
Number of days that Raeann read at first = 1 u
Number of pages that Raeann read at first
= 1 u x 13
= 13 u
Number of pages that Raeann read in the end = 13 u + 87
Number of days that Raeann read in the end = 1 u + 3
Number of pages that Raeann read in the end
= 17 x (1 u + 3)
= 17 u + 51
17 u + 51 = 13 u + 87
17 u - 13 u = 87 - 51
4 u = 36
1 u = 36 ÷ 4 = 9
Number of days that Raeann read in the end
= 1 u + 3
= 9 + 3
= 12
Answer(s): 12
