Answer:
3 days
Explanation:
Three hens lay 3 eggs in 3 days
We have to find the days in which 7 hens lay 7 eggs
Hen/egg=

Hen/egg=1
Using unitary method
1 hen lays 1 egg in 3 days
1 hen lays in 1 day =
eggs
7 hens lay 7/3 eggs in 1 day
7 hens lay 1 egg=
days
7 hens lay 7 eggs=

7 hens lay 7 eggs=3 days
Hence, 7 hens lay 7 eggs in 3 days