A certain nutritional study defined the N-score for one serving of a

Question

A certain nutritional study defined the N-score for one serving of a food to be P-Q, where P is the sum of 10 times the number of grams of fat and the number of kilocalories of energy provided per serving, and Q is 8 times the square of the number of grams of fiber provided per serving. If one serving of Food X provides m kilocalories of energy and n grams of fat and has an N-score of -28, then how many grams of fiber does one serving of Food X provide?

(1) One serving of Food X provides exactly 400 kilocalories of energy.

(2) One serving of a food that provides 120 kilocalories of energy, 3 grams of fiber, and the same number of grams of fat as one serving of Food X has an N-score of 0.

(1) One serving of Food X provides exactly 400 kilocalories of energy.

(2) One serving of a food that provides 120 kilocalories of energy, 3 grams of fiber, and the same number of grams of fat as one serving of Food X has an N-score of 0.

gmatophobia · Accepted Answer

N = P - Q

P = 10*f_t + e

f_t  → the number of grams of fat 
  e  → kilocalories of energy provided per serving

Q = 8*f_b^2

f_b  → the number of grams of fiber provided per serving

N = 10f_t + e - 8f_b^2

If one serving of Food X provides m kilocalories of energy and in grams of fat and has an N-score of -28

- 28 = 10f_t + m - 8f_b^2

Ques:  f_b  ?

Statement 1

(1) One serving of Food X provides exactly 400 kilocalories of energy.

m = 400

- 28 = 10f_t + 400 - 8f_b^2

While we have the value of m, we do not have the value of  f_t . Depending on the value of  f_t , the value of  f_b  will vary. Hence, the statement alone is not sufficient to find the value of  f_b . We can eliminate A and D.

Statement 2

(2) One serving of a food that provides 120 kilocalories of energy, 3 grams of fiber, and the same number of grams of fat as one serving of Food X has an N-score of 0.

0 = 10f_t + 120 - 8(3)^2

We can find the value of  f_t  from the above equation. This gives us the amount of fat in one serving of Food X.

- 28 = 10f_t + m - 8f_b^2

While we have the value of  f_t , we do not have the value of  m  to find the value of  f_b . Similar to Statement 1, depending on the value of  m , we can have different values of  f_b .

Hence, this statement alone is also insufficient to find the value of  f_b . We can eliminate B.

Combined

- 28 = 10f_t + m - 8f_b^2

From Statement 1, we know that  m = 400 , and from Statement 2 we can find the value of  f_t . As the equation now only has one unknown,  f_b , the value of  f_b  can be found by combining the information from both statements.

Hence, the statements combined help us to find the value of  f_b .

Option C

sayan640 · Answer

KarishmaB  ,  MartyMurray  I am taking 4/5 minutes to solve this qusetion/ these kinda question , when I am analyzing and solving for the first time . How do I reduce time ?

licrolicro · Answer

(2) One serving of a food that provides 120 kilocalories of energy, 3 grams of fiber, and the same number of grams of fat as one serving of Food X has an N-score of 0.

I find this statement really odd.

I would rephrase it like this:
When the N-score is 0, one serving of Food X includes 120 kilocalories of energy and 3 grams of fiber.

Pr4n · Answer

but unless it doesn't say that the FAT of this food is equal to the FAT of food X, you can't solve the question itself. Plus welcome to DI, half the issue or the thing you need to master is to read what it says and usually it ll be written in a manner to confuse so your paraphrasing skills are important and yes you have paraphrased it correctly but missed the point which is the most crucial.

aaronmart14 · Answer

Correct, but I think that he has simplify the    of this statement for e and that's it.

PeachSnapple1 · Answer

By solving Data Sufficient question type faster. Some people keep misleading others by saying that you only have 2 minutes to solve this kind of question. That's outright not true. But this kinda question should only take up 3 minutes, 4 and 5 is too long. If you feel it takes more than 3, just make an educated guess and move on. If time allows, you can always go back to it and change the answer if you need to.

sayan640

KarishmaB , MartyMurray I am taking 4/5 minutes to solve this qusetion/ these kinda question , when I am analyzing and solving for the first time . How do I reduce time ?

KarishmaB · Answer

The first thing to do here is to write the given relation.

N = 10 * Fat + (\frac{1}{10})*Calories - 8*Fiber^2

So to get a food's N score, we need 3 things - Fat, Calories and Fiber. We are given X's N score and we need to find its Fiber content so we need its Fat and Calories. If we plug in those in the equation above along with its N score, we will get the Fiber content it has.

(1) One serving of Food X provides exactly 400 kilocalories of energy.
  
Got Calories for X but not Fat. Not sufficient alone.

(2) One serving of a food that provides 120 kilocalories of energy, 3 grams of fiber, and the same number of grams of fat as one serving of Food X has an N-score of 0.
  
Got N, Calories and Fiber for a food which means we can get 'Fat' from here. This 'Fat' is the same as the Fat in X. 
Got 'Fat' for X, not Calories. Not sufficient alone.

Using both, got Fat and Calories for X. Sufficient.
(Actual calculations are not to be done)

Answer (C)

Robo_123 · Answer

Bunuel  I took over 4 mins here and honestly, I also got a bit lost with all this information.

Bunuel · Answer

The solution shown  here  should not take that much time.

A certain nutritional study defined the N-score for one serving of a

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A certain nutritional study defined the N-score for one serving of a

Prep Toolkit

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