SOLUTION: In a group of cows and chickens, the number of legs was 84 more then twice the number of heads. How many cows were there?

Question 449964: In a group of cows and chickens, the number of legs was 84 more then twice the number of heads. How many cows were there?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
In a group of cows and chickens, the number of legs was 84 more then twice the number of heads. How many cows were there?
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Let "L" = total # of legs.
Let "H" = total # of heads.
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L = 2H + 84
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# of legs = 4w + 2c where w = # of cows and c = # of chickens
# of heads = w + c
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Equations:
Since L = 2H + 84,
4w + 2c = 2(w+c) + 84
4w+2c = 2w+2c+84
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2w = 84
w = 42 (# of cows)
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Cheers,
Stan H.

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