The ratio of the number of girls to the number of boys in a class is 3 : 4. The ratio of the pupils in the class who scored merit to those who did not score merit is 3 : 1. The ratio of the girls who scored merit to those who did not score merit is 7 : 5. What is the ratio of boys who scored merit to the boys who did not score merit?
Girls |
Boys |
Total |
3x4 = 12 u |
4x4 = 16 u |
7x4 = 28 u |
Merit |
No merit |
Total |
3x7 = 21 u |
1x7 = 7 u |
4x7 = 28 u |
Girls |
Boys |
Total |
12 u |
16 u |
28 u |
Merit |
No Merit |
Merit |
No merit |
|
7 u |
5 u |
14 u |
2 u |
28 u |
The total number of pupils remains unchanged. Make the total number of pupils the same. LCM of 7 and 4 is 28.
Boys who scored merit : Boys who did not score merit
14 : 2
7 : 1
Answer(s): 7 : 1