The question is not clear, but I'll take a crack at what I think you're asking:
Driving at 20 km/hour, it takes 45/20 = 2.25 hours to cover 45 km.
That's 2 hours and 15 minutes.
It takes 2 hours and 15 minutes to cover a distance of 45 km at a speed of 20 km/h. This is calculated using the formula Time = Distance / Speed. The result can also be expressed as 2.25 hours.
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