Prep Test Doubt. Please Explain.

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Prep Test Doubt. Please Explain.

by tanvis1120 » Fri Aug 08, 2014 4:35 pm
I agree that option B is wrong. I intended to mark A instead.
However, the correct answer is C.


Target Q has Malik's pasta cup amount for 4 servings.
What did I assume?
Option 1: I considered that last time he prepared 4 servings and so this time it would be 2.
Hence, using ratios we can solve it. SUFFICIENT
(But the official answer does not seem to have assumed the Target Q as last time)

Option 2: INSUFFICIENT. There is no mention about the number of servings next time.
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by Brent@GMATPrepNow » Fri Aug 08, 2014 5:28 pm
Malik's recipe for 4 servings of a certain dish requires 1 1/2 cups of pasta. According to this recipe, what is the number of cups pasta that Malik will use the next time he prepares this dish?

1) The next time he prepare this dish, Malik will make half as many servings as he did the last time he prepared the dish

2) Malik used 6 cups of pasta the last time he prepared this dish
Target question: How many cups of pasta will Malik use the next time he prepares this dish?

Given: 4 servings of a certain dish requires 1 1/2 cups of pasta.
So, if we can determine the NUMBER OF DISH SERVINGS Malik prepares, we can determine how much pasta is required.

Statement 1: The next time he prepare this dish, Malik will make half as many servings as he did the last time he prepared the dish
We have no idea how many servings Malik made LAST time. So, we cannot determine the number of servings he'll make NEXT time.
So, statement 1 is NOT SUFFICIENT

Statement 2: Malik used 6 cups of pasta the last time he prepared this dish
This information does not help us determine how much pasta he'll need NEXT TIME.
So, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
Statement 2: Malik used 6 cups of pasta the last time
Statement 1: Next time, Malik will make half as many servings as he did the last time. If we makes half as many servings, Malik will need half as much pasta as he needed last time.
So, Malik will need 3 cups of pasta next time
Since we can answer the target question with certainty, the combined statements are SUFFICIENT

Answer = C

Cheers,
Brent
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by Brent@GMATPrepNow » Fri Aug 08, 2014 5:31 pm
tanvis1120 wrote: Target Q has Malik's pasta cup amount for 4 servings.
What did I assume?
Option 1: I considered that last time he prepared 4 servings and so this time it would be 2.
Hence, using ratios we can solve it. SUFFICIENT
The question tells us that the RECIPE for 4 servings requires 1 1/2 cups of pasta. It doesn't tell us how many servings Malik made last time.

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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