Marion had a collection of 2460 yellow, blue and black balls. After Marion gave away 340 yellow balls, the number of yellow balls was 240 fewer than the number of blue balls. Given that the number of black balls was twice as many as the number of blue balls, how many yellow balls did Marion have at first?
| |
Yellow balls |
Blue balls |
Black balls |
Total |
| Before |
1 u + 340 |
1 u + 240 |
2 u + 480 |
2460 |
| Change |
- 340 |
|
|
|
| After |
1 u |
1 u + 240 |
2 u + 480 |
|
Number of black balls in the end
= 2 x (1 u + 240)
= 2 u + 480
Total number of balls at first
= 1 u + 340 + 1 u + 240 + 2 u + 480
= 4 u + 1060
4 u + 1060 = 2460
4 u = 2460 - 1060
4 u = 1400
1 u = 1400 ÷ 4 = 350
Number of yellow balls that Marion had at first
= 1 u + 340
= 350 + 340
= 690
Answer(s): 690
