PSLE A box contained yellow balls and green balls. 60% of the balls were green. After some white balls were added to the box, 42% of the balls were green. What percentage of the balls in the box were white?
|
Green |
Yellow |
White |
Total |
Before |
3 u |
2 u |
|
5 u |
Change |
|
|
+ ? |
|
After |
42% |
28% |
|
100% |
60% =
60100 =
35 The number of green balls remains unchanged.
3 u → 42%
1 u → 42% ÷ 3 = 14%
2 u → 2 x 14 = 28%
Percentage of the balls in the box that were white
= 100% - 42% - 28%
= 30%
Answer(s): 30%