The average number of girls in 1A, 1B and 1C is 16. This is 2 more than the average number of boys in the 3 rooms.
37 of the total number of boys are in 1C.
12 of the number of boys in 1B is the same as
17 of the total number of boys in the 3 rooms. What fraction of the total number of girls in the 3 rooms is in 1A if there are 23 children in 1A?
| Boys in 1A |
Boys in 1B |
Boys in 1C |
Total boys |
| 4 |
3 |
7 |
| |
2 |
|
7 |
| 2 u |
2 u |
3 u |
7 u |
12 of boys in 1B =
17 of all boys
Boys in 1B : All boys = 2 : 7
Average number of boys
= 16 - 2
= 14
Total number of boys
= 3 x 14
= 42
7 u = 42
1 u = 42 ÷ 7 = 6
Number of boys in Room 1A
= 2 u
= 2 x 6
= 12
Number of girls in Room 1A
= 23 - 12
= 11
Total number of girls
= 3 x 16
= 48
Girls in 1ATotal girls =
1148 Answer(s):
1148 
