2 tons of concrete contains 800 kg of cement 600 kg of sand, the rest is crushed stone.

2 tons of concrete contains 800 kg of cement 600 kg of sand, the rest is crushed stone. How many percent of rubble is contained in concrete?

In the condition it is known that 2 tons of concrete contains 800 kg of cement and 600 kg of sand, and the rest is crushed stone. In order to find how many percent of crushed stone is contained in concrete, we will compose and solve the proportion.

Let’s take the weight of concrete as 100%. And using the variable x, we denote the percentage of crushed stone in the concrete.

Let’s calculate how much rubble is in concrete:

2,000 kg + (800 kg + 600 kg) = 2,000 – 1,400 = 600 kg.

2,000 kg of concrete – 100%;

600 kg of crushed stone – x%.

x = (600 * 100) / 2000 = 60,000/2000 = 30% of crushed stone in concrete.

Answer: 30%.