SOLUTION: There are 13 animals in the barn. Some are chickens and some are pigs. There are 40 legs in all. How many of each animal are there?

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Question 1021778: There are 13 animals in the barn. Some are chickens and some are pigs. There are 40 legs in all. How many of each animal are there?
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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C=chickens; P=pigs
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C+P=13
P=13-C
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4P+2C=40
4(13-C)+2C=40
52-4C+2C=40
-2C=-12
C=6
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P=13-C=13-6=7
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ANSWER: There are 6 chickens and 7 pigs.
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CHECK:(leg count)
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4P+2C=40
4(7)+2(6)=40
28+12=40
40=40