Official Guide Explanation:
Data Sufficiency #139

Background

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Solution and Metadata

Question: 139
Page: 285
Difficulty: 6 (Moderately Difficult)
Category 1: Arithmetic > Fractions >
Category 2: Arithmetic > Decimals >
Category 3: Arithmetic > Properties of Integers > Remainder

Explanation: Whether or not a decimal is terminating depends largely on the denominator: if the denominator is 2, for instance, the result will be an integer or a decimal of .5. (Other denominators of this type are 4, 5, 8, and 10.) However, any denominator that is a multiple of 3 will either be an integer or a non - terminating decimal, such as 0.33‾ .

Statement (1) is insufficient, as it provides no information about the denominator. Statement (2) is sufficient: if the denominator is 4, the decimal is either .0, .25, .5, or .75. In any of those cases, it is terminating. Choice (B) is correct.

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