The recipe calls for i cup of water to be mixed with 6 cups of cake mix. how much water should be mixed with 21 cups of cake mix?

1/x=6/21

What you need to do is set it up as a proportion.  1 cup to 6 cups cake mix, x cups to 21 cups cake mix.  

21/6 is 3.5

So 3.5 cups of water to 21 cups of cake mix (:

Hope this makes sense!

The recipe calls for 1 cup of water for every 6 cups of cake mix.
So, if you take 21 and divide it by 6, which is 3.5, that's how much water you should add (in cups).

Magic man is here, but unfortunately he is broke won’t you him out

Here for a good time of free question