The average number of pages Raeann read in a certain number of days was 18. In the next three days, Raeann read another 99 pages. As a result, the average number of pages she read increased to 23. How many days did Raeann read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 3 |
| Value |
18 |
23 |
| Number x value |
18 u |
23 u + 69 |
Number of days that Raeann read at first = 1 u
Number of pages that Raeann read at first
= 1 u x 18
= 18 u
Number of pages that Raeann read in the end = 18 u + 99
Number of days that Raeann read in the end = 1 u + 3
Number of pages that Raeann read in the end
= 23 x (1 u + 3)
= 23 u + 69
23 u + 69 = 18 u + 99
23 u - 18 u = 99 - 69
5 u = 30
1 u = 30 ÷ 5 = 6
Number of days that Raeann read in the end
= 1 u + 3
= 6 + 3
= 9
Answer(s): 9
