math

[gmat:(]

According to the directions on a can of frozen orange juice concentrate, i can of concentrate is to be mixed with 3 cans of water to make orange juice.how many 12 ounce cans of concentrate are required to prepare 200 6 ounce serving of orange juice?

A. 25
B. 34
C. 50
D. 67
E. 100

[Guest]

1 can of concentrate plus 3 cans of water equals 4/ So, concentrate is equal to 1/4 of the mixture. Now, the total mixture including concentrate and water is equal to 200 times 6ounce servings of orange juice to get 1200(total). Then, we need to figure out how much of the 1200 consists of concentrate only, so take 1/4 of 1200 and you get 300. Finally, divide 300(total concentrate in mixture) by 12-ounce cans to get the number of cans needed to make the mixture. The result is 25.

[bharri7]

Why must we do 200 * 6 = 1200? Would it be easier to say 6 ounces totaling 200 = 12 ounces totaling 100. Then 1/4 of 100 = 25?

Am I missing something? It feels like we can cut out a step.

[bharri7]

1 can of concentrate plus 3 cans of water equals 4/ So, concentrate is equal to 1/4 of the mixture. Now, the total mixture including concentrate and water is equal to 200 times 6ounce servings of orange juice to get 1200(total). Then, we need to figure out how much of the 1200 consists of concentrate only, so take 1/4 of 1200 and you get 300. Finally, divide 300(total concentrate in mixture) by 12-ounce cans to get the number of cans needed to make the mixture. The result is 25.

Why must we do 200 * 6 = 1200? Would it be easier to say 6 ounces totaling 200 = 12 ounces totaling 100. Then 1/4 of 100 = 25?

Am I missing something? It feels like we can cut out a step.

[esledge]

Same difference, Bharri. As long as you keep track of the multiplication and division, it doesn't matter much which order you use. I would just recommend writing it down, more to keep track of what the number you have computed represents (e.g. "the number of 12 ounce servings") than to keep track of the computations themselves.