PSLE
Lucy had a total of 126 red and green beads. She used 24 red beads and 70% of the green beads. After that, the ratio of the number of red beads to green beads Lucy had was 7 : 3.

1. What fraction of her green beads did Lucy use? Give your answer in the simplest form.
2. How many beads did Lucy have in the end?

	Red beads	Green beads	Total
Before	7 u + 24	10 u	17 u + 24
Change	- 24	- 7 u
After	7 u	3 u	10 u
Comparing red beads and green beads in the end	7	3	10

(a)
70% = ⁷⁰₁₀₀ = ⁷₁₀

Fraction of her green beads that Lucy used = ⁷₁₀

(b)
The number of green beads in the end is repeated.
Since the numbers are already the same, we do not need to use LCM to make them the same.

Number of green beads at first = 10 u
Number of red beads at first = 7 u + 24

Total number of beads at first
= 10 u + 7 u + 24
= 17 u + 24

17 u + 24 = 126
17 u = 126 - 24
17 u = 102

1 u = 102 ÷ 17 = 6

Number of green beads in the end = 3 u
Number of red beads in the end = 7 u

Total number of beads in the end
= 7 u + 3 u
= 10 u
= 10 x 6
= 60

Answer(s): (a)⁷₁₀; (b) 60