In a class, 6 girls jumped an average of 1.22 m for their standing broad jump in their fitness test. The boys in the same class jumped an average of 1.41 m in the same test. The total average of the whole class was 1.35 m. How many boys were there?
|
Girls |
Boys |
Children |
Number |
6 |
1 u |
1 u + 6 |
Value |
1.22 |
1.41 |
1.35 |
Total Value |
7.32 |
1.41 u |
1.35 u + 8.1 |
Total number of boys = 1 u
Total number of children = 1 u + 6
Total length that the girls jumped
= 6 x 1.22
= 7.32 m
Total length that the boys jumped
= 1 u x 1.41
= 1.41 u
Total length that the children jumped
= 1.35(1 u + 6)
= 1.35 u + 8.1
7.32 + 1.41 u = 1.35 u + 8.1
1.41 u - 1.35 u = 8.1 - 7.32
0.06 u = 0.78
1 u = 0.78 ÷ 0.06 = 13
Number of boys
= 1 u
= 13
Answer(s): 13