The average number of pages Anna read in a certain number of days was 20. In the next seven days, Anna read another 26 pages. As a result, the average number of pages she read decreased to 17. How many days did Anna read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 7 |
| Value |
20 |
17 |
| Number x value |
20 u |
17 u + 119 |
Number of days that Anna read at first = 1 u
Number of pages that Anna read at first
= 1 u x 20
= 20 u
Number of pages that Anna read in the end = 20 u + 26
Number of days that Anna read in the end = 1 u + 7
Number of pages that Anna read in the end
= 17 x (1 u + 7)
= 17 u + 119
20 u + 26 = 17 u + 119
20 u - 17 u = 119 - 26
3 u = 93
1 u = 93 ÷ 3 = 31
Number of days that Anna read in the end
= 1 u + 7
= 31 + 7
= 38
Answer(s): 38
