Jane had a collection of 2460 red, purple and white marbles. After Jane gave away 260 red marbles, the number of red marbles was 200 fewer than the number of purple marbles. Given that the number of white marbles was twice as many as the number of purple marbles, how many red marbles did Jane have at first?
| |
Red marbles |
Purple marbles |
White marbles |
Total |
| Before |
1 u + 260 |
1 u + 200 |
2 u + 400 |
2460 |
| Change |
- 260 |
|
|
|
| After |
1 u |
1 u + 200 |
2 u + 400 |
|
Number of white marbles in the end
= 2 x (1 u + 200)
= 2 u + 400
Total number of marbles at first
= 1 u + 260 + 1 u + 200 + 2 u + 400
= 4 u + 860
4 u + 860 = 2460
4 u = 2460 - 860
4 u = 1600
1 u = 1600 ÷ 4 = 400
Number of red marbles that Jane had at first
= 1 u + 260
= 400 + 260
= 660
Answer(s): 660
