Question

The time taken by a person to cover the 150 km per hour was 2 and half hours more than the time taken in the return journey. If he return at a speed of 10 kn per hour more than the speed while going, find the speed per hour in each direction.​

Answer 1

Step-by-step explanation:

⇒ Distance given =150km

⇒ Let the forward speed be x and the return speed will be x+10

We know that, Time=

speed

Distance

∴

x

150

=

x+10

150

+2.5

⇒ 150(x+10)−150x=2.5×x(x+10)

⇒ 150x+1500−150x=2.5x

2

+25x

⇒ 2.5x

2

+25x−1500=0

⇒ 25x

2

+250x−15000=0

⇒ x

2

+10x−600=0

⇒ x

2

+30x−20x−600=0

⇒ x(x+30)−20(x+30)=0

⇒ (x+30)(x−20)=0

The value of cannot be negative.

∴ Forward speed will be 20km/hr

⇒ Return speed =20+10=30km/hr

⇒ The required product =20×30=600km/hr