A car takes 5 hours to reach a destination by travelling at the speed of 60 km/hr. How long will it take when the car travels at the speed of 75 km/hr?
More the speed of car, lesser the time required. So, it is an inverse proportion.
Let the required time be x hours.
⇒ 5 × 60 = 75 × x
⇒ x = 
= 4 hours
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