PSLE Jaslyn had a bag of green beads and white beads in the ratio 17 : 9. She removed an equal number of green beads and white beads from the bag. The ratio of the number of green beads and white beads left in the bag became 9 : 4. What percentage of the beads were left in the bag?
|
Green beads |
White beads |
Difference |
Total |
Before |
17x5 = 85 u |
9x5 = 45 u |
8x5 = 40 u |
26x5 = 130 u |
Change |
- 13 u |
- 13 u |
|
|
After |
9x8 = 72 u |
4x8 = 32 u |
5x8 = 40 u |
13x8 = 104 u |
When Jaslyn removed an equal number of green beads and white beads, the difference between the number of green beads and white beads at first and in the end remains the same.
LCM of 8 and 5 is 40.
Percentage of the beads left in the bag
=
104130 x 100%
= 45 x 100%
= 80%
Answer: 80%