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A farmhouse shelters 11 animals. Some are goats and some are ducks.
Altogether there are 34 legs. How many of each animal are there?
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Let x be the number of goats.
Then the number of ducks is 11-x.
There is no need to remind that a goat has 4 legs, while a duck has only 2.
Write this simple equation counting the legs
4x + 2*(11-x) = 34.
Simplify and solve
4x + 22 - 2x = 34
4x - 2x = 34 - 22
2x = 12
x = 12/2 = 6.
ANSWER. 6 goats and 11-6 = 5 ducks.
Solved.
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