Question

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

Answer 1

______Heyy Buddy ❤_______

____Here's your Answer _________

Given;

Distance = 1500 km.

Speed = 100 km/hr.

Now,

Speed = Distance/ Time

=> Speed = 1500 / t.

=> Time = ( x - 1 / 2 )

Now,

New Speed = 1500 / (x - 1/2)

A.T.Q.

Speed New - Speed original = 100

=> [ 1500 / ( x - 1 / 2 ) ] - ( 1500 / x ) = 100

=> 150 [ ( 10 / x - 1 / 2 ] - 10 / x = 100 

=> 30 x -30 x +15 = 2x^2 - x

=> 15 = 2x^2 - x

=> 2x^2 - x -15 = 0

=> 2x^2 - ( 6 - 5)x - 15 =0

=> 2x ( x - 3 ) + 5 ( x - 3) = 0

=> 2x + 5 = 0. and. x - 3 =0

=> x = -5/2 ( Neglect)

=> x = 3.

The time taken by the Aeroplane is 3hrs.

=> Usual Speed = 1500 / 3

=> 500 km / hr.
✔✔✔

Answer 2

Answer:

Step-by-step explanation:

Distance = 1500 km.

Speed = 100 km/hr.

Now,

Speed = Distance/ Time

=> Speed = 1500 / t.

=> Time = ( x - 1 / 2 )

Now,

New Speed = 1500 / (x - 1/2)

A.T.Q.

Speed New - Speed original = 100

=> [ 1500 / ( x - 1 / 2 ) ] - ( 1500 / x ) = 100

=> 150 [ ( 10 / x - 1 / 2 ] - 10 / x = 100 

=> 30 x -30 x +15 = 2x^2 - x

=> 15 = 2x^2 - x

=> 2x^2 - x -15 = 0

=> 2x^2 - ( 6 - 5)x - 15 =0

=> 2x ( x - 3 ) + 5 ( x - 3) = 0

=> 2x + 5 = 0. and. x - 3 =0

=> x = -5/2 ( Neglect)

=> x = 3.

The time taken by the Aeroplane is 3hrs.

=> Usual Speed = 1500 / 3

=> 500 km / hr.

Hope it helps you