PSLE A box contained black marbles and green marbles. 40% of the marbles were green. After some brown marbles were added to the box, 26% of the marbles were green. What percentage of the marbles in the box were brown?
|
Green |
Black |
Brown |
Total |
Before |
2 u |
3 u |
|
5 u |
Change |
|
|
+ ? |
|
After |
26% |
39% |
|
100% |
40% =
40100 =
25 The number of green 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 brown
= 100% - 26% - 39%
= 35%
Answer(s): 35%