Problema Solution
A barn yard contains only ducks and pigs. If there are 30 heads and 80 legs, how many ducks are there?
Answer provided by our tutors
Let
x = the number of ducks
30 - x = the number of pigs (since each animal has 1 head the number of ducks and pigs altogether is 30)
Since each duck has 2 legs and each pig has 4 legs we have:
2x + 4(30 - x) = 80
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click here to see the equation solved for x
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x = 20 ducks
There are 20 ducks.