PSLE
Xuan had a total of 248 blue and yellow beads. She used 20 blue beads and 25% of the yellow beads. After that, the ratio of the number of blue beads to yellow beads Xuan had was 8 : 3.

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

	Blue	Yellow	Total
Before	8 u + 20	4 u	12 u + 20
Change	- 20	- 1 u
After	8 u	3 u	11 u
Comparing blue beads and yellow beads in the end	8	3	11

(a)
25% = ²⁵₁₀₀ = ¹₄

Fraction of her yellow beads that Xuan used = ¹₄

Fraction of her yellow beads that Xuan was left with
= 1 - ¹₄
= ³₄

(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 = 4 u
Number of blue beads at first = 8 u + 20

Total number of beads at first
= 4 u + 8 u + 20
= 12 u + 20

12 u + 20 = 248
12 u = 248 - 20
12 u = 228

1 u = 228 ÷ 12 = 19

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

Number of more blue beads than yellow beads that Xuan had in the end
= 8 u - 3 u
= 5 u
= 5 x 19
= 95

Answer(s): (a)³₄; (b) 95