Eva had the same number of purple, black and green erasers at first. After giving some purple and black erasers and 57 green erasers away, Eva had 173 erasers left. There were 4 times as many purple erasers as black erasers left. The number of green erasers left was 34 fewer than the number of purple erasers left. How many green erasers did she have at first?
| |
Black |
Purple |
Green |
Total |
| Before |
4 u + 23 |
4 u + 23 |
4 u + 23 |
|
| Change |
- 3 u - 23 |
- 23 |
- 57 |
|
| After |
1 u |
4 u |
4 u - 34 |
173 |
Eva had the same number of purple, black and green erasers at first.
Total number of erasers in the end
= 1 u + 4 u + 4 u - 34
= 9 u - 34
9 u - 34 = 173
9 u = 173 + 34
9 u = 207
1 u = 207 ÷ 9 = 23
Number of green erasers that Eva had at first
= 4 u - 34 + 57
= 4 u + 23
= 4 x 23 + 23
= 115
Answer(s): 115
