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by Brent@GMATPrepNow » Fri Aug 09, 2013 12:18 am
According to the directions on 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
This can be solved using equivalent ratios.
The first part tells that, for every 1 can of concentrate, we can make 4 cans of juice.
Let's be even more generic, for 1 volume of concentrate, we can make 4 volumes of juice.

Okay, now notice that we have a problem with the volume mismatch in the question. It involves 12-ounce cans of concentrate and 6-ounce servings.
So, let's reword the question. Instead of making 200 6-ounce servings of juice, let's make 100 12-ounce servings of juice. We're still making the same amount of juice.

We're now asking, "How many 12-ounce cans of the concentrate are required to prepare 100 12-ounce serving of orange juice?

We'll solve this question using equivalent ratios.

(volume of concentrate)/(volume of juice): 1/4 = x/100

Solve for x to get [spoiler]x=25[/spoiler]
So, the answer is A

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by [email protected] » Fri Aug 09, 2013 5:37 pm
Hi prashanth.guru,

Brent's ratio explanation is right on. Since this is a ratio question, you CAN use the ratio in different ways to get the same correct answer.

In this case, we're told to mix 1 12-ounce can of concentrate with 3 12-ounce cans of water to make juice:

(1)(12) + (3)(12) = 48 ounces of juice per 1 can of concentrate

Since we're asked for 6-ounce servings of juice, we can deduce:

1 can of concentrate gives us 48 ounces of juice gives us 8 6-ounce servings.

So, 1 can = 8 servings

We want 200 servings....

200/8 = 25 cans

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