The average number of girls in 3A, 3B and 3C is 10. This is 4 more than the average number of boys in the 3 rooms.
19 of the total number of boys are in 3C.
12 of the number of boys in 3B is the same as
19 of the total number of boys in the 3 rooms. What fraction of the total number of girls in the 3 rooms is in 3A if there are 26 children in 3A?
Boys in 3A |
Boys in 3B |
Boys in 3C |
Total boys |
8 |
1 |
9 |
|
2 |
|
9 |
6 u |
2 u |
1 u |
9 u |
12 of boys in 3B =
19 of all boys
Boys in 3B : All boys = 2 : 9
Average number of boys
= 10 - 4
= 6
Total number of boys
= 3 x 6
= 18
9 u = 18
1 u = 18 ÷ 9 = 2
Number of boys in Room 3A
= 6 u
= 6 x 2
= 12
Number of girls in Room 3A
= 26 - 12
= 14
Total number of girls
= 3 x 10
= 30
Girls in 3ATotal girls =
1430 =
715 Answer(s):
715