I have a question about the following problem.
Fill the gap with appropriate words from the following options.
It won’t take ( ) 15 minutes to walk there, so put your shoes on and let’s go.
(1) at least, (2) at most, (3) less than, (4) more than.
The answer is (4). What I can’t understand is why (1) is not another answer. ‘at least 15’ means ‘the minimum is 15’, which means ‘more than 15’. Yet, ‘more than’ is correct and ‘at least’ is not. Why?