Official Guide Explanation:
Problem Solving #114

Background

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Solution and Metadata

Question: 114
Page: 76
Difficulty: 5 (Moderate)
Category 1: Algebra > Linear Equations-One Unk >
Category 2: Word Problems > Other >
Category 3: Arithmetic > Percents > other

Explanation: Salesperson A's compensation can be written algebraically as follows, where s stands for sales: A = 360 + (0.06)(s - 1000). Salesperson B's compensation is much simpler: B = (0.08)s. To find the value of s when the salespeople earn the same amount, set A and B equal to each other and solve:

360 + (0.06)(s - 1000) = (0.08)s

360 + 0.06s - 60 = 0.08s

300 = 0.02s

s = 300(50) = 15,000, choice (C).

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