PSLE
At first, a container contained 5 green marbles and some blue beads. After some green marbles were added, 25 of the marbles were blue. After 36 white marbles were added to the container and now, 29 of the beads were blue. What was the number of green marbles added?
|
Blue marbles |
Green marbles |
White marbles |
Total |
Before |
2 u |
5 |
0 |
|
Change 1 |
|
+ ? |
|
+ ? |
After 1 |
2 u |
3 u |
0 |
5 u |
Change 2 |
|
|
+ 36 |
+ 4 u |
After 2 |
2 u |
3 u |
4 u |
9 u |
Some green marbles were added at first. However, when 36 white marbles were added, the number of green marbles remains unchanged.
Number of white marbles added
= 9 u - 5 u
= 4 u
4 u = 36
1 u = 36 ÷ 4 = 9
Number of green marbles added
= 3 u - 5
= 3 x 9 - 5
= 27 - 5
= 22
Answer(s): 22