The average number of girls in 5A, 5B and 5C is 13. This is 5 more than the average number of boys in the 3 rooms.
18 of the total number of boys are in 5C.
12 of the number of boys in 5B is the same as
18 of the total number of boys in the 3 rooms. What fraction of the total number of girls in the 3 rooms is in 5A if there are 32 children in 5A?
Boys in 5A |
Boys in 5B |
Boys in 5C |
Total boys |
7 |
1 |
8 |
|
2 |
|
8 |
5 u |
2 u |
1 u |
8 u |
12 of boys in 5B =
18 of all boys
Boys in 5B : All boys = 2 : 8
Average number of boys
= 13 - 5
= 8
Total number of boys
= 3 x 8
= 24
8 u = 24
1 u = 24 ÷ 8 = 3
Number of boys in Room 5A
= 5 u
= 5 x 3
= 15
Number of girls in Room 5A
= 32 - 15
= 17
Total number of girls
= 3 x 13
= 39
Girls in 5ATotal girls =
1739 Answer(s):
1739