PSLE Linda had a basket of grey beads and pink beads in the ratio 13 : 7. She removed an equal number of grey beads and pink beads from the basket. The ratio of the number of grey beads and pink beads left in the basket became 4 : 1. What percentage of the beads were left in the basket?
|
Grey beads |
Pink beads |
Difference |
Total |
Before |
13x1 = 13 u |
7x1 = 7 u |
6x1 = 6 u |
20x1 = 20 u |
Change |
- 5 u |
- 5 u |
|
|
After |
4x2 = 8 u |
1x2 = 2 u |
3x2 = 6 u |
5x2 = 10 u |
When Linda removed an equal number of grey beads and pink beads, the difference between the number of grey beads and pink beads at first and in the end remains the same.
LCM of 6 and 3 is 6.
Percentage of the beads left in the basket
=
1020 x 100%
= 12 x 100%
= 50%
Answer: 50%