Question

Concrete is made by mixing cement and sand in the ratio 1:3. How much sand would be needed to make 120 tonnes of concrete?

A: 30 tonnes B: 40 tonnes C: 90 tonnes D: 480 tonnes E: None of these

Answer 1

Explanation:

sand is 3 parts out of (1+3 = 4) parts or 3/4 of the cement mixture

3/4 * 120 = 90 tonnes of sand