The average number of pages Kimberly read in a certain number of days was 19. In the next seven days, Kimberly read another 31 pages. As a result, the average number of pages she read decreased to 16. How many days did Kimberly read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 7 |
| Value |
19 |
16 |
| Number x value |
19 u |
16 u + 112 |
Number of days that Kimberly read at first = 1 u
Number of pages that Kimberly read at first
= 1 u x 19
= 19 u
Number of pages that Kimberly read in the end = 19 u + 31
Number of days that Kimberly read in the end = 1 u + 7
Number of pages that Kimberly read in the end
= 16 x (1 u + 7)
= 16 u + 112
19 u + 31 = 16 u + 112
19 u - 16 u = 112 - 31
3 u = 81
1 u = 81 ÷ 3 = 27
Number of days that Kimberly read in the end
= 1 u + 7
= 27 + 7
= 34
Answer(s): 34
