In a class, 6 girls jumped an average of 1.41 m for their standing broad jump in their fitness test. The boys in the same class jumped an average of 1.58 m in the same test. The total average of the whole class was 1.52 m. How many boys were there?
|
Girls |
Boys |
Children |
Number |
6 |
1 u |
1 u + 6 |
Value |
1.41 |
1.58 |
1.52 |
Total Value |
8.46 |
1.58 u |
1.52 u + 9.12 |
Total number of boys = 1 u
Total number of children = 1 u + 6
Total length that the girls jumped
= 6 x 1.41
= 8.46 m
Total length that the boys jumped
= 1 u x 1.58
= 1.58 u
Total length that the children jumped
= 1.52(1 u + 6)
= 1.52 u + 9.12
8.46 + 1.58 u = 1.52 u + 9.12
1.58 u - 1.52 u = 9.12 - 8.46
0.06 u = 0.66
1 u = 0.66 ÷ 0.06 = 11
Number of boys
= 1 u
= 11
Answer(s): 11