Answer:
47 ducks and 7 cows
Step-by-step explanation:
Ducks have 2 legs and cows have 4 legs.
If all the animals are ducks,
number of legs= 54(2)= 108
Difference in number of legs= 122 -108= 14
Difference in no. of legs per animal= 4 -2 = 2
Number of cows=14 ÷2 = 7
Number of ducks= 54-7= 47
Thus, he have 47 ducks and 7 cows.
Let's check:
Total number of feet= 7(4)+ 47(2) = 122 ✓
You could also first assume that all the animals are cows. The answer would be the same.