The average number of pages Xandra read in a certain number of days was 19. In the next seven days, Xandra read another 38 pages. As a result, the average number of pages she read decreased to 14. How many days did Xandra read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 7 |
| Value |
19 |
14 |
| Number x value |
19 u |
14 u + 98 |
Number of days that Xandra read at first = 1 u
Number of pages that Xandra read at first
= 1 u x 19
= 19 u
Number of pages that Xandra read in the end = 19 u + 38
Number of days that Xandra read in the end = 1 u + 7
Number of pages that Xandra read in the end
= 14 x (1 u + 7)
= 14 u + 98
19 u + 38 = 14 u + 98
19 u - 14 u = 98 - 38
5 u = 60
1 u = 60 ÷ 5 = 12
Number of days that Xandra read in the end
= 1 u + 7
= 12 + 7
= 19
Answer(s): 19
