Garima takes the underground train to work and uses an escalator at the railway station. If Garima runs up 8 steps of the escalator, then it takes her 30.0 seconds to reach the top of the escalator. If she runs up 15 steps of the escalator, then it takes her only 12.5 seconds to reach the top.

How many seconds would it take Garima to reach the top if she did not run up any steps of the escalator at all?