A customer wants to put in a concrete driveway that is 10" thick. How much concrete would it take to pour a driveway that measures 18' by 42'? Express your answer in cubic yards.

Respuesta :

Answer: 22.59 yd^3

Step-by-step explanation:

First the volume of a cuboid whose measurements are:

L = length, W = width and T = thiknes is:

V = L*W*T.

We want to calculate the volume of a shape that is:

10'' thick, 18' wide and 42' long.

This notation is:

(') = feet

('') = inches

The first step is to write our 3 numbers in the same units, then we can use that:

1 inch = 0.083 ft.

Then 10 inches are equal to:

10'' = 10*(0.083 ft) = 0.83 ft = 0.83'

Then the volume of concrete needed will be:

V = 0.83ft*18ft*42ft = 627.48 ft^3

But we want this expressed in yd^3

1ft = 0.33 yd

then

1ft^3 = (0.33 yd)^3 = 0.036 yd^3

then 627.48 ft^3 can be written as:

627.48 ft^3 = 627.48*( 0.036 yd^3) = 22.59 yd^3