Pit together ratio Vs. real. ratio of 1:3 means that the final product has 4 ratio units. These should be equivalent to 200*6 = 1200 ounces in real, so each ratio unit is worth 1200/4 = 3oo ouncesin real.
Since the orange juic is only 1 ratio unit of the total 4, you need 1*300= 300 ounces of concentrate (and 3*300 = 900 ounces of water). As a final step, figure out how many 12-ounce cans you need to make 300 ounces: 300/12 = 25 cans.
Alternative method:
plug in the answers back into the question. If you use 25 cans of 12 ounces each, you have 12*25=300 ounces of conctrate, which is combined with three times that amount in water, or 300*3=900 ounces water (ratio of 1:3). The resulting total is 900+300=1200 ounces - exactly the 200 servings of 6 ounces each you need, so A is the right answer. Any greater answer will result in too much orange juice.
