Question

15 workers can lay a road of length 4km in 4 hours . then how many workers can lay a road of length 8km in 8 hours?
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Answer 1

Answer:

it is the case of indirect variation or inverse variation

so try to find it

Answer 2

15 workers can lay a road of length 4km in 4 hours . Then "15" workers can lay a road of length 8km in 8 hours.

* A road of 4km can be build in 4hrs by 15 workers.

A road of 1km can be build in 4hrs by 15/4 workers.

A road of 1km can be build in 1hrs by (15/4)*4 = 15 workers.

A road of 8km can be build in 1hrs by 15*8= 120 workers.

Finally, A road of 8km can be build in 8hrs by 120/8 = 15workers.