Question

A passenger, while boarding the plane, slipped from stairs and got hurt. The pilot took the passenger in the emergency clinic at the airport for treatment.Due to this, plane got delayed by half an hour.To reach the destination 1500 km away in time, so that the passenger could catch the connecting flight, the speed of plane was increased by 250km/hr than the usual speed .What is the usual speed of plane?

Answer 1

Here's ur ans. my frd:

Hope This Helps :)

Answer 2

Solution :-

Let the original speed of train be x km/hr

New speed = (x + 250) km/hr

We know that,

Time = Distance / Speed

Given : A plane left 30 minutes or 1/2 hours later than the scheduled time.

According to the question,

=> 1500/x - 1500/(x + 250) = 1/2

=> (1500x + 37500 - 1500x)/x(x + 250) = 1/2

=> 2(37500) = x(x + 250)

=> 75000 = x² + 250x

=> x² + 250x - 75000 = 0

=> x² + 1000x - 750x - 75000 = 0

=> x(x + 1000) - 750(x + 1000) = 0

=> (x - 750) (x + 1000) = 0

=> x = 750 or x = - 1000

∴ x ≠ - 1000 (Because speed can't be negative)

Hence,

Its usual speed = 750 km/hr