PSLE
Abi had a total of 165 pink and silver beads. She used 22 pink beads and 25% of the silver beads. After that, the ratio of the number of pink beads to silver beads Abi had was 7 : 3.

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

	Pink beads	Silver beads	Total
Before	7 u + 22	4 u	11 u + 22
Change	- 22	- 1 u
After	7 u	3 u	10 u
Comparing pink beads and silver beads in the end	7	3	10

(a)
25% = ²⁵₁₀₀ = ¹₄

Fraction of her silver beads that Abi used = ¹₄

(b)
The number of silver 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 silver beads at first = 4 u
Number of pink beads at first = 7 u + 22

Total number of beads at first
= 4 u + 7 u + 22
= 11 u + 22

11 u + 22 = 165
11 u = 165 - 22
11 u = 143

1 u = 143 ÷ 11 = 13

Number of silver beads in the end = 3 u
Number of pink beads in the end = 7 u

Total number of beads in the end
= 7 u + 3 u
= 10 u
= 10 x 13
= 130

Answer(s): (a)¹₄; (b) 130