It takes 4 and 1/2 minutes to fill an empty aquarium to a depth of 3/5 meters.

what is the unit rate per meter?

answer as a fraction or mixed number in simplest form

To fill 1/5 meters it takes:
3/5 divided by 4 1/2
=3/5 divided by 9/2
=3/5 x 2/9
=2/15

To fill 5/5 or 1 meter it takes:
2/15 x 5
=10/15
=2/3
Therefore, it takes 2/3 minutes to fill an empty aquarium to a depth of 5/5 or 1 meter.