Pat and Mila used the following concrete mix formula for their house: 4 parts sand, 4 parts gravel, 3 parts cement and 1 part water. What is the ratio of water to cement?

Sagot :

We have:
Sand:Gravel:Cement:Water
  4    :   4    :    3      :    1

We just take the ratio of water to cement which is 1:3.
The answer is:
1 part water:3 parts cement

because in this mixture, you only used 1 part of water and then 3 parts of cement so since we are only needing water to cement, ignore the other two. Hope this helps =)