The average number of pages Julie read in a certain number of days was 16. In the next four days, Julie read another 96 pages. As a result, the average number of pages she read increased to 20. How many days did Julie read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 4 |
| Value |
16 |
20 |
| Number x value |
16 u |
20 u + 80 |
Number of days that Julie read at first = 1 u
Number of pages that Julie read at first
= 1 u x 16
= 16 u
Number of pages that Julie read in the end = 16 u + 96
Number of days that Julie read in the end = 1 u + 4
Number of pages that Julie read in the end
= 20 x (1 u + 4)
= 20 u + 80
20 u + 80 = 16 u + 96
20 u - 16 u = 96 - 80
4 u = 16
1 u = 16 ÷ 4 = 4
Number of days that Julie read in the end
= 1 u + 4
= 4 + 4
= 8
Answer(s): 8
