Barbara had a collection of 1740 gold, yellow and black beads. After Barbara gave away 340 gold beads, the number of gold beads was 120 fewer than the number of yellow beads. Given that the number of black beads was twice as many as the number of yellow beads, how many gold beads did Barbara have at first?
| |
Gold beads |
Yellow beads |
Black beads |
Total |
| Before |
1 u + 340 |
1 u + 120 |
2 u + 240 |
1740 |
| Change |
- 340 |
|
|
|
| After |
1 u |
1 u + 120 |
2 u + 240 |
|
Number of black beads in the end
= 2 x (1 u + 120)
= 2 u + 240
Total number of beads at first
= 1 u + 340 + 1 u + 120 + 2 u + 240
= 4 u + 700
4 u + 700 = 1740
4 u = 1740 - 700
4 u = 1040
1 u = 1040 ÷ 4 = 260
Number of gold beads that Barbara had at first
= 1 u + 340
= 260 + 340
= 600
Answer(s): 600
