Question

If the speed of an aeroplane is increased by
2ookm/her, the time required to cover a
distance of 2000km is reduced by 30min.
Find the original speed of the aeroplane​

Answer 1

Answer:

Solution

verified

Verified by Toppr

Let the original speed of the aircraft be x km/hr.

then new speed =(x−200) km.hr

Duration of flight at original speed =(

x

600

)hr

Duration of fight at reduced speed =(

x−200

600

)hr

∴

x−200

600

−

x

600

=

2

1

⇒

x(x−200)

600x−600(x−20)

=

2

1

⇒

x

2

−200x

120000

=

2

1

⇒x

2

−200x−240000=0⇒x

2

−600x+400x−240000=0

⇒(x−600)(x+400)=0⇒x=600orx=−400⇒x=600

So, the origianl speed of the aircraft was 600km/hr

hence, duration of flight =(

x

600

)hr=(

60

600

)hr=1hr