PSLE
Kylie had a total of 141 black and orange beads. She used 50 black beads and 75% of the orange beads. After that, the ratio of the number of black beads to orange beads Kylie had was 9 : 1.

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

	Black	Orange	Total
Before	9 u + 50	4 u	13 u + 50
Change	- 50	- 3 u
After	9 u	1 u	10 u
Comparing black beads and orange beads in the end	9	1	10

(a)
75% = ⁷⁵₁₀₀ = ³₄

Fraction of her orange beads that Kylie used = ³₄

Fraction of her orange beads that Kylie was left with
= 1 - ³₄
= ¹₄

(b)
The number of orange 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 orange beads at first = 4 u
Number of black beads at first = 9 u + 50

Total number of beads at first
= 4 u + 9 u + 50
= 13 u + 50

13 u + 50 = 141
13 u = 141 - 50
13 u = 91

1 u = 91 ÷ 13 = 7

Number of orange beads in the end = 1 u
Number of black beads in the end = 9 u

Number of more black beads than orange beads that Kylie had in the end
= 9 u - 1 u
= 8 u
= 8 x 7
= 56

Answer(s): (a)¹₄; (b) 56