In a class, 14 girls jumped an average of 1.48 m for their standing broad jump in their fitness test. The boys in the same class jumped an average of 1.5 m in the same test. The total average of the whole class was 1.49 m. How many boys were there?
|
Girls |
Boys |
Children |
Number |
14 |
1 u |
1 u + 14 |
Value |
1.48 |
1.5 |
1.49 |
Total Value |
20.72 |
1.5 u |
1.49 u + 20.86 |
Total number of boys = 1 u
Total number of children = 1 u + 14
Total length that the girls jumped
= 14 x 1.48
= 20.72 m
Total length that the boys jumped
= 1 u x 1.5
= 1.5 u
Total length that the children jumped
= 1.49(1 u + 14)
= 1.49 u + 20.86
20.72 + 1.5 u = 1.49 u + 20.86
1.5 u - 1.49 u = 20.86 - 20.72
0.01 u = 0.14
1 u = 0.14 ÷ 0.01 = 14
Number of boys
= 1 u
= 14
Answer(s): 14