Vanessa had a collection of 2200 silver, grey and black beads. After Vanessa gave away 300 silver beads, the number of silver beads was 130 fewer than the number of grey beads. Given that the number of black beads was thrice as many as the number of grey beads, how many silver beads did Vanessa have at first?
| |
Silver beads |
Grey beads |
Black beads |
Total |
| Before |
1 u + 300 |
1 u + 130 |
3 u + 390 |
2200 |
| Change |
- 300 |
|
|
|
| After |
1 u |
1 u + 130 |
3 u + 390 |
|
Number of black beads in the end
= 3 x (1 u + 130)
= 3 u + 390
Total number of beads at first
= 1 u + 300 + 1 u + 130 + 3 u + 390
= 5 u + 820
5 u + 820 = 2200
5 u = 2200 - 820
5 u = 1380
1 u = 1380 ÷ 5 = 276
Number of silver beads that Vanessa had at first
= 1 u + 300
= 276 + 300
= 576
Answer(s): 576
