A farmer has ducks and cows in his barn. Counting heads, there are 12. Counting legs, there are 34. How many ducks are there?
7
If all 12 animals were ducks, there would be 12 x 2 = 24 legs. Each cow adds 2 extra legs (4 instead of 2). We have 34 - 24 = 10 extra legs. Dividing 10 by 2 gives 5 cows. Therefore, there are 12 - 5 = 7 ducks.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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