PSLE At first, a container contained 51 gold beads and some grey beads. After some gold beads were removed,
25 of the beads were grey. After 52 white beads were added to the container and now,
29 of the beads were grey. What was the number of gold beads removed?
|
Grey beads |
Gold beads |
White beads |
Total |
Before |
2 u |
51 |
0 |
|
Change 1 |
|
- ? |
|
+ ? |
After 1 |
2 u |
3 u |
0 |
5 u |
Change 2 |
|
|
+ 52 |
+ 4 u |
After 2 |
2 u |
3 u |
4 u |
9 u |
Some gold beads were removed at first. However, when 52 white beads were added, the number of gold beads remains unchanged.
Number of white beads added
= 9 u - 5 u
= 4 u
4 u = 52
1 u = 52 ÷ 4 = 13
Number of gold beads removed
= 51 - 3 u
= 51 - 3 x 13
= 51 - 39
= 12
Answer(s): 12