Official Guide Explanation:
Problem Solving #48




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Solution and Metadata

Question: 48
Page: 68
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Fractions >

Explanation: First, recognize that (3/8) is less than (1/2), and three of the fractions are greater than (1/2). That means that our middle number will be the smallest of these three fractions, (9/16), (17/24), and (3/4). The quickest way to compare fractions like this is to find a common denominator, in this case 48 (which is divisible by 4, 16, and 24). Adjust the fractions as follows:

(9/16)((3/3)) = (27/48)

(17/24)((2/2)) = (34/48)

(3/4)((12/12)) = (36/48)

The smallest of these is (9/16), so that must be the middle number of the sequence. The correct choice is (E).

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