Chickens & rabbits
The question
A farmyard has 32 ducks and sheep in it. Counting every leg comes to 96.
How many are sheep?
Assume they are all the same, then fix it
animals:32· legs:96
32×2=64
96−64=32
32÷2=16
- There are 32 animals altogether, standing on 96 legs.
- Pretend every one of them has two legs: 32 × 2 = 64 legs.
- The real count is 96, so the pretend one is short by 96 − 64 = 32 legs.
- Each four-legged animal adds 2 more legs. So the number to turn is 32 ÷ 2 = 16 sheep.
How it works.
- 01
There are 32 animals altogether, standing on 96 legs.
- 02
Pretend every one of them has two legs: 32 × 2 = 64 legs.
- 03
The real count is 96, so the pretend one is short by 96 − 64 = 32 legs.
- 04
Each four-legged animal adds 2 more legs. So the number to turn is 32 ÷ 2 = 16 sheep.