He finished the job in an hour

[lagoo]

1. He finished the job in an hour.
2. He will finish the job in an hour.

In sentence (1), does it mean no more than 60 minutes, and most likely about 55-60 minutes?
In sentence (2), does it mean a little more than 60 minutes, for example, 60-62 minutes?

 

[Rover_KE]

Here, 'an hour' means 'approximately 60 minutes'.

If it's important to stipulate precisely 60 minutes, say 'He finished/will finish the job in exactly one hour'.

 

[GoesStation]

1 tells us that the job took him about an hour to complete. The second could mean that we expect the job to require about an hour or that it will be done about an hour from now. Michelangelo will finally finish painting that fresco in an hour! He's been working on it for years!

 

[Tdol]

The tense doesn't change the time required.