PSLE A box contained brown balls and gold balls. 60% of the balls were gold. After some silver balls were added to the box, 15% of the balls were gold. What percentage of the balls in the box were silver?
|
Gold |
Brown |
Silver |
Total |
Before |
3 u |
2 u |
|
5 u |
Change |
|
|
+ ? |
|
After |
15% |
10% |
|
100% |
60% =
60100 =
35 The number of gold balls remains unchanged.
3 u → 15%
1 u → 15% ÷ 3 = 5%
2 u → 2 x 5 = 10%
Percentage of the balls in the box that were silver
= 100% - 15% - 10%
= 75%
Answer(s): 75%