PSLE A box contained gold marbles and blue marbles. 40% of the marbles were blue. After some red marbles were added to the box, 26% of the marbles were blue. What percentage of the marbles in the box were red?
|
Blue |
Gold |
Red |
Total |
Before |
2 u |
3 u |
|
5 u |
Change |
|
|
+ ? |
|
After |
26% |
39% |
|
100% |
40% =
40100 =
25 The number of blue marbles remains unchanged.
2 u → 26%
1 u → 26% ÷ 2 = 13%
3 u → 3 x 13 = 39%
Percentage of the marbles in the box that were red
= 100% - 26% - 39%
= 35%
Answer(s): 35%