Jade had a collection of 2150 brown, green and purple marbles. After Jade gave away 310 brown marbles, the number of brown marbles was 210 fewer than the number of green marbles. Given that the number of purple marbles was thrice as many as the number of green marbles, how many brown marbles did Jade have at first?
| |
Brown marbles |
Green marbles |
Purple marbles |
Total |
| Before |
1 u + 310 |
1 u + 210 |
3 u + 630 |
2150 |
| Change |
- 310 |
|
|
|
| After |
1 u |
1 u + 210 |
3 u + 630 |
|
Number of purple marbles in the end
= 3 x (1 u + 210)
= 3 u + 630
Total number of marbles at first
= 1 u + 310 + 1 u + 210 + 3 u + 630
= 5 u + 1150
5 u + 1150 = 2150
5 u = 2150 - 1150
5 u = 1000
1 u = 1000 ÷ 5 = 200
Number of brown marbles that Jade had at first
= 1 u + 310
= 200 + 310
= 510
Answer(s): 510
