The number of houses that can be served by a water pipe vari

The number of houses that can be served by a water pipe varies directly as the square of the diameter of the pipe. A water pipe that has a 10-centimeter diameter can supply 40 houses.

How many houses can be served by a water pipe that has 50 centimeter diameter

What size of water pipe is needed for a new subdivision of 1440 houses

Solution

houses(h) that can be served by a water pipe varies directly as the square of the diameter(d)

h =k d²

10-centimeter diameter can supply 40 houses

40=k(10)²

k =40/100

k =0.4

h =0.4 d²

number of houses that can be served by a water pipe that has 50 centimeter diameter=0.4*50²

number of houses that can be served by a water pipe that has 50 centimeter diameter=1000houses

for water pipe that needed for a new subdivision of 1440 houses

1440=0.4d²

d²=1440/0.4

d =60 cm

diameter =60cm