Math, asked by omsingh190805, 2 months ago

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 speed by
100 km/h from the usual speed. Find its usual speed.​

Answers

Answered by krishnasharma1138
1

Answer:

Let the usual speed be x km/hr.

Then, the speed taken =(x+100) km/hr

Distance =1500 km

Usual time =

usual speed

distance

=

x

1500

hrs

Time taken =

x+100

1500

hrs

It is given that Time taken=Usual time−0.5 hrs

x

1500

x+100

1500

=

2

1

x(x+100)

1500(x+100)−1500x

=

2

1

⇒x

2

+100x=1500×100×2

⇒x

2

+100x−300000=0

⇒x=

2

−100±

100

2

+4×300000

=

2

−100±1100

=500 or−600

Since speed cannot be negative, x=500 km/hr

∴ The usual speed of the plane is 500 km/hr.

Answered by jasmeenkaurdourka
0

Answer:

Let the usual speed be x km/hr.

Then, the speed taken =(x+100) km/hr

Distance =1500 km

Usual time =

usual speed

distance

=

x

1500

hrs

Time taken =

x+100

1500

hrs

It is given that Time taken=Usual time−0.5 hrs

x

1500

x+100

1500

=

2

1

x(x+100)

1500(x+100)−1500x

=

2

1

⇒x

2

+100x=1500×100×2

⇒x

2

+100x−300000=0

⇒x=

2

−100±

100

2

+4×300000

=

2

−100±1100

=500 or−600

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