Official Guide Explanation:
Problem Solving #98




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Solution and Metadata

Question: 98
Page: 74
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Properties of Integers > Factors and Multiples

Explanation: The greatest common divisor (or factor) of two numbers cannot be larger than the two numbers. In fact, the largest the GCF can be is equal to the smaller of the two numbers, if the smaller number is a factor of the larger number (x = 6 and y = 12, for instance). So, (E) must be correct: since both x and y are positive, x + y must be greater than both x and y, and thus cannot be the GCF.

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