In 1 minute 3/7 of a bucket is filled. The rest of the bucket can be filled in

Question: In 1 minute 3/7 of a bucket is filled. The rest of the bucket can be filled in -

Solution:
Filled of the bucket 3/7 part.
Remaining = 1 - (3/7) = 4/7 part.

3/7 part is filled in = 1 min
∴ 1 part is filled in = 7/3 min
So, 4/7 part is filled in = (7/3) × (4/7) min
= 4/3 minutes