A car takes 2 hours to reach a destination by travelling at 60 km/hr. How long will it take while travelling at 80 km/hr?

More the speed, lesser the time to travel. So, it is an inverse proportion.

Let the required time be x hr.

⇒ 2 × 60 = 80 × x

⇒ x = = 1.5 hours = 1hour 30 minutes