PSLE At first, a container contained 63 blue beads and some grey beads. After some blue beads were removed,
58 of the beads were grey. After 100 purple beads were added to the container and now,
513 of the beads were grey. What was the number of blue beads removed?
|
Grey beads |
Blue beads |
Purple beads |
Total |
Before |
5 u |
63 |
0 |
|
Change 1 |
|
- ? |
|
+ ? |
After 1 |
5 u |
3 u |
0 |
8 u |
Change 2 |
|
|
+ 100 |
+ 5 u |
After 2 |
5 u |
3 u |
5 u |
13 u |
Some blue beads were removed at first. However, when 100 purple beads were added, the number of blue beads remains unchanged.
Number of purple beads added
= 13 u - 8 u
= 5 u
5 u = 100
1 u = 100 ÷ 5 = 20
Number of blue beads removed
= 63 - 3 u
= 63 - 3 x 20
= 63 - 60
= 3
Answer(s): 3