Problem Solving

Thanks in advance for your help!

Q: According to the directions on a can of frozen orange juice concentrate, 1 can of concentrate is to be mixed with 3 cans of water to make orange juice. How many 12-ounce cans of the concentrate are required to prepare 200 6-ounce servings of orange juice?

25
34
50
67
100

I know the answer, but how do you get to it?

Thanks,

LizinCali