PSLE Min had a basket of gold beads and pink beads in the ratio 18 : 7. She removed an equal number of gold beads and pink beads from the basket. The ratio of the number of gold beads and pink beads left in the basket became 3 : 1. What percentage of the beads were left in the basket?
|
Gold beads |
Pink beads |
Difference |
Total |
Before |
18x2 = 36 u |
7x2 = 14 u |
11x2 = 22 u |
25x2 = 50 u |
Change |
- 3 u |
- 3 u |
|
|
After |
3x11 = 33 u |
1x11 = 11 u |
2x11 = 22 u |
4x11 = 44 u |
When Min removed an equal number of gold beads and pink beads, the difference between the number of gold beads and pink beads at first and in the end remains the same.
LCM of 11 and 2 is 22.
Percentage of the beads left in the basket
=
4450 x 100%
= 2225 x 100%
= 88%
Answer: 88%