Data Sufficiency

candygal79 wrote: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 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