Find answer to the following question?

Question

There are two glass of water. When a bacterium is dropped into glass, it will double in a minute. 2 bacteria are dropped into the 1st glass and one into the second. The second glass is full in an 1 hour and at what time the 1st glass would be filled?

Answer 1

59 minutes.

Starting with 1 bacterium, it takes 1 minute to become 2.  Thereafter the rate is the same for the glass starting with 2 bacteria.  So starting with 2 only shaves one minute off the time.

Answer 2

half an hour

Answer 3

that's easy..it's a half hour.. right?

Answer 4

it takes 59 minutes...