The average number of pages Elyse read in a certain number of days was 15. In the next three days, Elyse read another 25 pages. As a result, the average number of pages she read decreased to 11. How many days did Elyse read in total?
|
At first |
In the end |
Number |
1 u |
1 u + 3 |
Value |
15 |
11 |
Number x value |
15 u |
11 u + 33 |
Number of days that Elyse read at first = 1 u
Number of pages that Elyse read at first
= 1 u x 15
= 15 u
Number of pages that Elyse read in the end = 15 u + 25
Number of days that Elyse read in the end = 1 u + 3
Number of pages that Elyse read in the end
= 11 x (1 u + 3)
= 11 u + 33
15 u + 25 = 11 u + 33
15 u - 11 u = 33 - 25
4 u = 8
1 u = 8 ÷ 4 = 2
Number of days that Elyse read in the end
= 1 u + 3
= 2 + 3
= 5
Answer(s): 5