SOLUTION: Larry paid 2520 for a watch, a radio, and a calculator. The watch cost 180 more than the radio and the radio cost 120 more than the calculator. How much did each item cost?

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Larry paid 2520 for a watch, a radio, and a calculator. The watch cost 180 more than the radio and the radio cost 120 more than the calculator. How much did each item cost?      Log On


   

Question 977625: Larry paid 2520 for a watch, a radio, and a calculator. The watch cost 180 more than the radio and the radio cost 120 more than the calculator. How much did each item cost?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Larry paid 2520 for a watch, a radio, and a calculator. The watch cost 180 more than the radio and the radio cost 120 more than the calculator. How much did each item cost?
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Equatiions:
w + r + c = 2520
w = r + 180
r = c + 120
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Substitute for w and c and solve for "r"::
(r+180) + r + (r-120) = 2520
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3r + 60 = 2520
3r = 2460
r = 820 (cost of the radio)
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w = r + 180 = 1000 (cost of the watch)
c = r-120 = 700 (cost of the calculator)
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Cheers,
Stan H.