Marion has a bag containing some silver and red beads. If she removes 2 silver beads, 30% of the beads in the bag are red. If she removes another 15 red beads, 20% of the beads in the bag are red. How many silver beads are in the bag?
| |
Silver beads |
Red beads |
| Before |
28 u + 2 |
12 u |
| Change 1 |
- 2 |
|
| After 1 |
7x4 =
28 u |
3x4 =
12 u |
| Change 2 |
|
- 15 |
| After 2 |
4x7 =
28 u |
1x7 =
7 u |
30% =
30100 =
31020% =
20100 =
15The number of silver beads remains unchanged at the second change when she removes another 15 red beads. Make the number of silver beads the same at the second change. LCM of 7 and 4 is 28.
Number of red beads removed
= 12 u - 7 u
= 5 u
5 u = 15
1 u = 15 ÷ 5 = 3
Number of silver beads at first
= 28 u + 2
= 28 x 3 + 2
= 84 + 2
= 86
Answer(s): 86
