PSLE
Jen had a total of 237 purple and yellow beads. She used 39 purple beads and 70% of the yellow beads. After that, the ratio of the number of purple beads to yellow beads Jen had was 8 : 3.

1. What fraction of her yellow beads was Jen left with? Give your answer in the simplest form.
2. How many more purple beads than yellow beads did Jen have in the end?

	Purple	Yellow	Total
Before	8 u + 39	10 u	18 u + 39
Change	- 39	- 7 u
After	8 u	3 u	11 u
Comparing purple beads and yellow beads in the end	8	3	11

(a)
70% = ⁷⁰₁₀₀ = ⁷₁₀

Fraction of her yellow beads that Jen used = ⁷₁₀

Fraction of her yellow beads that Jen was left with
= 1 - ⁷₁₀
= ³₁₀

(b)
The number of yellow 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 yellow beads at first = 10 u
Number of purple beads at first = 8 u + 39

Total number of beads at first
= 10 u + 8 u + 39
= 18 u + 39

18 u + 39 = 237
18 u = 237 - 39
18 u = 198

1 u = 198 ÷ 18 = 11

Number of yellow beads in the end = 3 u
Number of purple beads in the end = 8 u

Number of more purple beads than yellow beads that Jen had in the end
= 8 u - 3 u
= 5 u
= 5 x 11
= 55

Answer(s): (a)³₁₀; (b) 55