Question

To make a grey paint the ratio is 1:3 white to black. To make 24 litres of grey paint, How much white and black paint do we need?

Answer 1

1:3 means for every 1 liter or white paint you will need 3 or the black

This could also be represented as a ratio of 3/4 black paint and 1/4 white

So
24 x 3/4= black paint
18 liters of black paint