Official Guide Explanation:
Problem Solving #124




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Solution and Metadata

Question: 124
Page: 77
Difficulty: 6 (Moderately Difficult)
Category 1: Word Problems > Rate Problems > other
Category 2: Algebra > Equations >
Category 3: Arithmetic > Ratio and Proportion >

Explanation: To find the difference in price person between the cost when 10 people share it and when 16 people share it, first find the cost in each case. If the total cost is x and 10 people take the trip, the cost per person is ((x)/10). If 16 people take the trip, the cost per person is ((x)/16). The difference, then, is ((x)/10) - ((x)/16) = ((8x)/80) - ((5x)/80) = ((3x)/80), choice (E).

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