Question 706519
): a farmer owns a farm with chickens and pigs. the farmer counted 17 heads and 60 legs. how many chickens and pigs are there? 
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# of legs equation: 2c+4p = 60
# of heads equation: c + p = 17
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Modify:
c + 2p = 30
c + p  = 17
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Subtract and solve for "p":
p = 13 (# of pigs)
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Solve for "c":
c + p = 17
c + 13 = 17
c = 4 (# of chickens)
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Cheers,
Stan H.
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