Question 197771
A customer walks into an electronics store and buys four MP3 players and six sets of headphones, paying $740. A second customer buys five MP3 players and four sets of headphones, and pays $785. How much does an MP3 player cost? How much does a set of headphones cost? 
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Equations:
4M + 6H = 740
5M + 4H = 785
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Use any method you know to solve this 
system of equations to get:
M = $125 (price of an MP3)
H = $40 (price of headphones)
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Cheers,
Stan H.