Question

Dry concrete can be made by mixing sand, gravel and cement

in the ratio 1: 2: 3. If you want 1800 kg of dry concrete,
how much of each will you need? Give your answers in
kilograms (kg).

Answer 1

To make 1800 kg of dry concrete in the ratio 1:2:3, you will need 300 kg of sand, 600 kg of gravel, and 900 kg of cement.

Step-by-step explanation:

To calculate how much sand, gravel, and cement you will need to make 1800 kg of dry concrete in the ratio 1:2:3, you need to find the total number of parts in the ratio. In this case, it is 1+2+3 = 6 parts. Then, divide the total weight of the concrete (1800 kg) by 6 to find the weight of one part. 1800 kg / 6 = 300 kg.

Therefore, you will need 1 part of sand, 2 parts of gravel, and 3 parts of cement, each weighing 300 kg. So, you will need 300 kg of sand, 600 kg of gravel, and 900 kg of cement to make 1800 kg of dry concrete.

Answer 2

Sand is 1/6 of the mixture. 1/6 x 1800 = 300 kg
Gravel is 2/6 of mixture. 2/6 x 1800 = 600 kg
Cement is 3/6 of mixture. 3/6 x 1800 = 900 kg