. A water pipe that has a 10- centimeter diameter can supply 20 houses. How many houses can be served by a water pipe that has a 20centimeter diameter?

Question

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Answer 1

Ignoring several factors, such as friction, pipe layout, loss of water pressure, and so on, the volume of water flowing through a pipe is related to the cross sectional area of the pipe.

 

in the case of a 5cm pipe, the area = pi x r², which is 3.1415 x (2.5cm)² = 19.6cm²

 

in the case of a 10cm pipe, the area = pi x r², which is 3.1415 x (5cm)² = 78.5cm²

 

so, the 10cm pipe will carry 78.5/19.6 or 4 times as much water.

 

so, a pipe of that size could supply 80 houses.