Question

A plane left 30 minutes late than its scheduled time and in order to reach of destination 1500 km away in time, it had to increase its speed by 100 km/h from the usual speed. Find its usual speed.

Answer 1

Let usual speed of the plane be x km/hr.

Speed of plane = 500 km/hr.

Detailed Answer:

Let the speed of plane be x km/hr

Time taken to cover 1500 km

If x + 600 = 0 ⇒ x = – 600 speed can not be negative.

If x – 500 = 0

⇒ x = 500

∴ Speed of the plane = 500 km/hr