Bob the builder is making 480 kg of concrete mix concrete is made by mixing cement, sand and gravel in the ratio 1 : 3 : 4

how much sand does he need?

180 kg

Step-by-step explanation:

The ratio is

cement : sand : gravel

    1       :    3     :    4

If he used 1 kg cement, 3 kg sand, and 4 kg gravel, he'd get 8 kg of concrete.

He wants to make 480 kg of concrete.

480/8 = 60

He needs 60 times more concrete than the numbers in the ratio.

60 * 3 kg = 180 kg

180 kg

12

step-by-step explanation:

a triangle's   full angle is 180 degrees so 180 - 156 = 24. 24/2=12

is there supposed to be a diagram or a graph for this one? ?

step-by-step explanation: