PSLE Jen had a total of 182 black and green beads. She used 32 black beads and 50% of the green beads. After that, the ratio of the number of black beads to green beads Jen had was 8 : 1.
- What fraction of her green beads was Jen left with? Give your answer in the simplest form.
- How many more black beads than green beads did Jen have in the end?
|
Black |
Green |
Total |
Before |
8 u + 32 |
2 u |
10 u + 32 |
Change |
- 32 |
- 1 u |
|
After |
8 u |
1 u |
9 u |
Comparing black beads and green beads in the end |
8
|
1
|
9
|
(a)
50% =
50100 =
12 Fraction of her green beads that Jen used =
12 Fraction of her green beads that Jen was left with
= 1 -
12=
12(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 = 2 u
Number of black beads at first = 8 u + 32
Total number of beads at first
= 2 u + 8 u + 32
= 10 u + 32
10 u + 32 = 182
10 u = 182 - 32
10 u = 150
1 u = 150 ÷ 10 = 15
Number of green beads in the end = 1 u
Number of black beads in the end = 8 u
Number of more black beads than green beads that Jen had in the end
= 8 u - 1 u
= 7 u
= 7 x 15
= 105
Answer(s): (a)
12; (b) 105