Risa had the same number of brown, black and red pens at first. After giving some brown and black pens and 59 red pens away, Risa had 250 pens left. There were 2 times as many brown pens as black pens left. The number of red pens left was 40 fewer than the number of brown pens left. How many red pens did she have at first?
| |
Black |
Brown |
Red |
Total |
| Before |
2 u + 19 |
2 u + 19 |
2 u + 19 |
|
| Change |
- 1 u - 19 |
- 19 |
- 59 |
|
| After |
1 u |
2 u |
2 u - 40 |
250 |
Risa had the same number of brown, black and red pens at first.
Total number of pens in the end
= 1 u + 2 u + 2 u - 40
= 5 u - 40
5 u - 40 = 250
5 u = 250 + 40
5 u = 290
1 u = 290 ÷ 5 = 58
Number of red pens that Risa had at first
= 2 u - 40 + 59
= 2 u + 19
= 2 x 58 + 19
= 135
Answer(s): 135
