PSLE Warren kept his black and white marbles in two boxes. The ratio of the number of black to white marbles in the first box was 1 : 2 and it was 1 : 8 in the second box. The two boxes contained the same number of marbles. What fraction of Warren's marbles were black marbles?
First box |
Second box |
1x9 9 u |
1x9 9 u |
3x3 |
9x1 |
Black |
White |
Black |
White |
1x3 |
2x3 |
1x1 |
8x1 |
3 u |
6 u |
1 u |
8 u |
The total number of marbles in the first box and the second box is the same. Make the total number of marbles in each box the same. LCM of 3 and 9 is 9.
Total number of black marbles
= 3 u + 1 u
= 4 u
Total number of marbles
= 9 u + 9 u
= 18 u
Fraction of Warren's marbles that were black marbles
=
418 =
29 Answer(s):
29