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 4.1 QC X-ray 4.2 QC Fundamentals

 4.3 QC Step Method 4.4 Practice Problems
QC X-ray
Here’s a typical QC, complete with directions. Don’t attempt the question just yet—we’ll get to it in just a bit.

Directions: Each of the following questions consists of two quantities, one in Column A and one in Column B. You are to compare the quantity in Column A with the quantity in Column B and decide whether:

(A) The quantity in Column A is greater.

(B) The quantity in Column B is greater.

(C) The two quantities are equal.

(D) The relationship cannot be determined from the information given.

In a question, there may be additional information, centered above the two columns, that concerns one or both of the quantities to be compared. A symbol that appears in both columns represents the same thing in Column A as it does in Column B.

A certain bread recipe calls for water, flour, and yeast to be mixed in a ratio of 4:5:2 ounces, respectively.

 Column A Column B The amount of flour needed to make 220 ounces of bread according to the recipe 100 ounces
(A) The quantity in Column A is greater.
(B) The quantity in Column B is greater.
(C) The two quantities are equal.
(D) The relationship cannot be determined from the information given.
The directions are fairly self-explanatory: You’re given two quantities and asked to figure out whether one is definitely bigger than the other, if they’re equal, or if you don’t have enough information to tell. The quantities may be absolute numbers or may include variables—a difference of no small importance when it comes to strategy, as you’ll soon see. Sometimes the test makers will provide additional information above the columns as part of the question, sometimes not. In this case, the additional information is the sentence describing the ingredient ratios for the bread recipe. Any additional symbols or variables provided mean the same thing for both quantities.
QC answer choices are always the same, so it pays to memorize them right now. And notice the major difference between these questions and all of the other math questions on the GRE: There are only four choices. Hey, that improves your odds right there, even if you have to take a blind guess. Of course, the purpose of this chapter is to help you keep blind guessing to a minimum.
 Jump to a New ChapterIntroductionMeet GRE MathMath 101Problem SolvingQuantitative ComparisonsData InterpretationMeet GRE VerbalSentence CompletionsReading ComprehensionAntonymsAnalogiesMeet GRE EssaysThe Issue EssayThe Argument EssayPracticing with Practice TestsThe Future of the GRETop 15 GRE Test Day TipsFinal Thought
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