PSLE At first, a container contained 77 purple beads and some green beads. After some purple beads were removed,
37 of the beads were green. After 15 brown beads were added to the container and now,
310 of the beads were green. What was the number of purple beads removed?
|
Green beads |
Purple beads |
Brown beads |
Total |
Before |
3 u |
77 |
0 |
|
Change 1 |
|
- ? |
|
+ ? |
After 1 |
3 u |
4 u |
0 |
7 u |
Change 2 |
|
|
+ 15 |
+ 3 u |
After 2 |
3 u |
4 u |
3 u |
10 u |
Some purple beads were removed at first. However, when 15 brown beads were added, the number of purple beads remains unchanged.
Number of brown beads added
= 10 u - 7 u
= 3 u
3 u = 15
1 u = 15 ÷ 3 = 5
Number of purple beads removed
= 77 - 4 u
= 77 - 4 x 5
= 77 - 20
= 57
Answer(s): 57