If 45 milliliters of water are required to mix 100 grams of plaster how many milliliters would you need for 250 grams of plaster?

Answer 1

Ratio water : plaster = 45 ml : 100 g

You need to find how many lots of 100g are in 250 g and that tells you how many lots of 45 ml you need:

lots required = 250g / 100g

→ need 45 ml × 250g / 100g = 45 ml × 2.5 = 112.5 ml of water.

Answer 2

The required quantity is 112.5 millilitres.

Answer 3

250/100 times 45 = 112.5 milliliters