AlgebraMediumHeads and legs on a farm
Algebra practice question
A farmyard holds chickens and goats — 24 animals in all, with 68 legs among them. How many goats are there?
Answer: 10
If all 24 were chickens there would be 48 legs; the 20 extra legs come from goats at 2 extra each, so there are 10 goats.
Common wrong answers
- If you answered 12
- Check: 12 goats and 12 chickens gives 48 + 24 = 72 legs, too many.
- If you answered 14
- 14 is the number of chickens; the goats number 10.
- If you answered 20
- 20 is the count of extra legs beyond all-chickens; each goat adds 2, giving 10 goats.
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