IR Explained: Q22: Nutritional Quantities

July 30, 2012

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This post is part of a series--IR Explained--that walks through the sample Integrated Reasoning questions provided in the latest edition of the GMAT Official Guide.

Don't be overwhelmed by the sheer volume of numbers in this Table Analysis question. You'll only be asked three Yes/No questions, and those items can only address so many of the numbers.

Also, don't worry too much about the specificity of serving size. The introductory paragraph refers to "240 mL" simply to make clear that all the servings are the same amount, making the questions less complicated.

While most of the columns are numbers, note the "yes/no" nature of the column "Cooked." When there is one column that stands out from the rest like this, you can be sure that the questions will focus on it more heavily than the others.

22A asks you to compare the median amount of protein in the uncooked vegetables to the median amount in the cooked vegetables. First, sort by "Cooked."

There are five uncooked vegetables, with protein amounts of 3, 1, 1, 1, 1. When those numbers are placed in order, the middle term is 1, so the median is 1. There are 10 cooked vegetables, with protein amounts of 5, 3, 5, 2, 5, 2, 3, 3, 5, 2. In order, that's 2, 2, 2, 3, 3, 3, 5, 5, 5, 5, with the two middle terms bolded. The median, then, is 3.

1, the median amount of protein for the uncooked vegetables, is 1/3 the median amount of protein for the cooked vegetables, so 22A is Yes.

22B once again proposes a multiple of three. Here you are asked to compare carbohydrates in cooked corn to the median of all other options. The carbohydrates per serving of cooked corn is 32.

Next, you could find the median of the other 14 options. Instead, consider what the question asks. If 32 is exactly 3 times the median of the other 14, the median of the other 14 is 32/3, or 10 2/3. But the median is either a whole number (one of the integers in the carbohydrate column) or the average of two whole numbers, such as 10.5 or 4.5. It is impossible for the median to be 10 2/3! Thus, no calculations are needed--22B is No.

In 22C, begin by sorting by total fiber. 8 of the 15 options have less than 3.0g of fiber. Confirm in the carbohydrate column that none of those 8 have more than 10g of carbohydrate. 22C is Yes.

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About the author: Jeff Sackmann has written many GMAT preparation books, including the popular Total GMAT Math, Total GMAT Verbal, and GMAT 111. He has also created explanations for problems in The Official Guide, as well as 1,800 practice GMAT math questions.

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