Gwen had the same number of red, purple and brown marbles at first. After giving some red and purple marbles and 66 brown marbles away, Gwen had 169 marbles left. There were 2 times as many red marbles as purple marbles left. The number of brown marbles left was 16 fewer than the number of red marbles left. How many brown marbles did she have at first?
| |
Purple |
Red |
Brown |
Total |
| Before |
2 u + 50 |
2 u + 50 |
2 u + 50 |
|
| Change |
- 1 u - 50 |
- 50 |
- 66 |
|
| After |
1 u |
2 u |
2 u - 16 |
169 |
Gwen had the same number of red, purple and brown marbles at first.
Total number of marbles in the end
= 1 u + 2 u + 2 u - 16
= 5 u - 16
5 u - 16 = 169
5 u = 169 + 16
5 u = 185
1 u = 185 ÷ 5 = 37
Number of brown marbles that Gwen had at first
= 2 u - 16 + 66
= 2 u + 50
= 2 x 37 + 50
= 124
Answer(s): 124
