Question 1031986: Mrs. McDonald has a farm with ducks and pigs. There are 27 heads and 84 legs. How many ducks and pigs are on Mrs. McDonald's farm? Found 2 solutions by stanbon, ikleyn:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Mrs. McDonald has a farm with ducks and pigs. There are 27 heads and 84 legs. How many ducks and pigs are on Mrs. McDonald's farm?
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Legs Eq:: 2d + 4p = 84 legs
Heads Eq: d + p = 27 heads
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Modify for elimination::
d + 2p = 42
d + p = 27
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Subtract and solve for "p"::
p = 15 (# of pigs)
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Solve for "d"
d = 27-15 = 12 (# of ducks)
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Cheers,
Stan H.
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