Answer:
he has 20 chickens
Explanation:
i was testing with it. 20 dog legs divided by 4 (since dogs have 4 legs) equals 5. 5 times 4 (since 4 times the amount of dogs) is 20. then to check, 20 times 2 (since chickens have 2 feet) is 40. 20 dog legs plus 40 chicken legs. makes sense. again, 20 chickens.