The average number of pages Tina read in a certain number of days was 16. In the next three days, Tina read another 84 pages. As a result, the average number of pages she read increased to 22. How many days did Tina read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 3 |
| Value |
16 |
22 |
| Number x value |
16 u |
22 u + 66 |
Number of days that Tina read at first = 1 u
Number of pages that Tina read at first
= 1 u x 16
= 16 u
Number of pages that Tina read in the end = 16 u + 84
Number of days that Tina read in the end = 1 u + 3
Number of pages that Tina read in the end
= 22 x (1 u + 3)
= 22 u + 66
22 u + 66 = 16 u + 84
22 u - 16 u = 84 - 66
6 u = 18
1 u = 18 ÷ 6 = 3
Number of days that Tina read in the end
= 1 u + 3
= 3 + 3
= 6
Answer(s): 6
