PSLE A box contained gold balls and blue balls. 60% of the balls were blue. After some white balls were added to the box, 45% of the balls were blue. What percentage of the balls in the box were white?
|
Blue |
Gold |
White |
Total |
Before |
3 u |
2 u |
|
5 u |
Change |
|
|
+ ? |
|
After |
45% |
30% |
|
100% |
60% =
60100 =
35 The number of blue balls remains unchanged.
3 u → 45%
1 u → 45% ÷ 3 = 15%
2 u → 2 x 15 = 30%
Percentage of the balls in the box that were white
= 100% - 45% - 30%
= 25%
Answer(s): 25%