Malik's recipe for 4 servings of a certain dish requires 3/2

C

4 servings - 3/2 pasta

1. X/2 with X unknown
Not Sufficient
2. He used 6 cups of pasta last time, means he prepared the recipe for 16 servings
Not Sufficient

Together
Sufficient

Hi Guys

Statement 1 says - (1) The next time he prepares this dish, Malik will make half as many servings as he did the last time he prepared the dish.

I interpreted this as next time he will prepare half of 4 servings which is 2 so he will need half of 1.5 cups of pasta !!

Then answer is A

Please advise

Me too..
Bunuel's pointed a VERY GOOD reminder that the statements never contradict each other (I almost forgot!)

Thanks Bunuel.

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Nice questions. I missed the word "last time".

messed up question for sure!

4 servings of dish require 1.5 cups of pasta
=> 1 serving of dish require 1.5/4 cups of pasta
(1) is insufficient because it just says: "Malik will make half as many servings as he did the last time he prepared the dish.". However, we don't know how many servings he prepared last time. Since we don't know the servings, we can't find how much pasta is required. So, insufficient.

(2) says Malik used 6 cups of pasta the last time he prepared this dish. Just looking at this statement in isolation, if 6 cups of pasta the last time, we clearly can't say how many cups of pasta Malik will use the "next time". So, insufficient.

Combining (1) and (2), we know that he used 6 cups of pasta the last time and Malik will make half as many servings as he did the last time. That being the case, Malik will clearly require 3 cups of pasta next time. Sufficient.

Hence, C.

Looks like a Critical Reasoning Problem haha

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 past 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

A detailed explanation can be found in this video:
https://www.youtube.com/watch?v=rb1Z3EnrzpY

For a DS question, always ask, "What would I need to know in order to answer this question?" Here, what we need to know is the number of servings in the next recipe - that information would tell us everything we need to know in order to answer the initial question.

This is a proportion question, but (like most word problems!) there's a trap answer. In this case, the trap answer its answer A - we're told what the recipe is, be we aren't told how many serving there were in the LAST recipe! That rules out answers A and D.

In combination, however, statements (1) and (2) together do tell us everything we need to know.

Answer C

Statement I
The next time he prepares this dish, Malik will make half as many servings as he did the last time he prepared the dish.
We do not know how many servings he prepared last time. Therefore, we cannot use the relation given in the question data.
(insufficient)
.
Statement II
1.5 cups of pasta = 4 serving
Multiplying both sides by 4, we get
=>6 cups of pasta = 16 serving.
We know how many servings he prepared last time, but, we do not know how many he will prepare this time.
(insufficient)

Combining statements I and II
From statement I, we know the relationship between the servings last time and the servings this time.
From statement II, we know that he prepared 16 servings last time.
Hence, we can say that Malik requires 3 cups of pasta since he will make 8 servings this time.
(sufficient)

Option C is the answer.

Thanks,
Clifin J Francis,
GMAT SME

Bunuel, avigutman, MartyTargetTestPrep, can we say that for each serving, Malik used 3/8 cups of pasta. We get this number by dividing 3/2 into 4 uniform servings.

Can we make that assumption?

Thank you!

Absolutely, CrushTHYGMAT. Though, technically, that's an inference, not an assumption

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