The average number of pages Fiona read in a certain number of days was 19. In the next three days, Fiona read another 25 pages. As a result, the average number of pages she read decreased to 15. How many days did Fiona read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 3 |
| Value |
19 |
15 |
| Number x value |
19 u |
15 u + 45 |
Number of days that Fiona read at first = 1 u
Number of pages that Fiona read at first
= 1 u x 19
= 19 u
Number of pages that Fiona read in the end = 19 u + 25
Number of days that Fiona read in the end = 1 u + 3
Number of pages that Fiona read in the end
= 15 x (1 u + 3)
= 15 u + 45
19 u + 25 = 15 u + 45
19 u - 15 u = 45 - 25
4 u = 20
1 u = 20 ÷ 4 = 5
Number of days that Fiona read in the end
= 1 u + 3
= 5 + 3
= 8
Answer(s): 8
