PSLE Ivory had a total of 177 blue and pink beads. She used 23 blue beads and 30% of the pink beads. After that, the ratio of the number of blue beads to pink beads Ivory had was 4 : 7.
- What fraction of her pink beads did Ivory use? Give your answer in the simplest form.
- How many beads did Ivory have in the end?
|
Blue beads |
Pink beads |
Total |
Before |
4 u + 23 |
10 u |
14 u + 23 |
Change |
- 23 |
- 3 u |
|
After |
4 u |
7 u |
11 u |
Comparing blue beads and pink beads in the end |
4 |
7 |
11 |
(a)
30% =
30100 =
310 Fraction of her pink beads that Ivory used =
310 (b)
The number of pink 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 pink beads at first = 10 u
Number of blue beads at first = 4 u + 23
Total number of beads at first
= 10 u + 4 u + 23
= 14 u + 23
14 u + 23 = 177
14 u = 177 - 23
14 u = 154
1 u = 154 ÷ 14 = 11
Number of pink beads in the end = 7 u
Number of blue beads in the end = 4 u
Total number of beads in the end
= 4 u + 7 u
= 11 u
= 11 x 11
= 121
Answer(s): (a)
310; (b) 121