A mixture of concrete is made up of sand and cement in a ratio of 5:3. How many cubic feet of each are needed to make 160 cubic feet of concrete mix?

We need 100 cubic feet of sand and 60 cubic feet of cement to make 160 cubic feet of concrete mix

Solution:

Given that, mixture of concrete is made up of sand and cement in a ratio of 5 : 3

To find: Cubic feet of sand and cement needed for 160 cubic feet of concrete mix

From given statement,

Sand : cement = 5 : 3

Let the sand needed be 5x

Let the cement needed be 3x

We need 160 cubic feet of concrete mix

Therefore,

sand needed + cement needed = 160

5x + 3x = 160

8x = 160

x = 20

Thus, sand needed = 5x = 5 (20) = 100

cement needed = 3x = 3920) = 60

Thus we need 100 cubic feet of sand and 60 cubic feet of cement