PSLE Xylia had a basket of white beads and green beads in the ratio 16 : 9. She removed an equal number of white beads and green beads from the basket. The ratio of the number of white beads and green beads left in the basket became 5 : 1. What percentage of the beads were left in the basket?
|
White beads |
Green beads |
Difference |
Total |
Before |
16x4 = 64 u |
9x4 = 36 u |
7x4 = 28 u |
25x4 = 100 u |
Change |
- 29 u |
- 29 u |
|
|
After |
5x7 = 35 u |
1x7 = 7 u |
4x7 = 28 u |
6x7 = 42 u |
When Xylia removed an equal number of white beads and green beads, the difference between the number of white beads and green beads at first and in the end remains the same.
LCM of 7 and 4 is 28.
Percentage of the beads left in the basket
=
42100 x 100%
= 2150 x 100%
= 42%
Answer: 42%