Question

A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h . How long will it take when the car travels at the speed of 80 km/h ?​

Answer 1

Question:

A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h . How long will it take when the car travels at the speed of 80 km/h ?​

Answer:

It takes 1 hour 30 minutes to cover the distance.

Given:

Speed = 60 km/h

Time = 2 hours.

To find:

Time taken to cover the same distance at a speed of 80 km/h.

Explanation:

Case-1:

Speed = (Distance/time)

∴ Distance = (Speed × Time)

                 = (60×2) km

                 = 120 km.

∴ The car travels a distance of 120 km.

Case-2:

Distance = 120 km.

Speed = 80 km/h

Distance= (Speed× Time)

∴ Time = (Distance/Speed)

           = (120/80)

           =(3/2) [∵ Dividing 120 and 80 by 40.]

           = 1 hour (1×60/2) minutes [∵ 1 hour = 60 minutes.]

           = 1 hour 30 minutes.

∴ It will take 1 hour 30 minutes to cover the distance.

Answer 2

Hey Pretty Stranger!

$\large \bold \red{Here \: you \: go \: !}$

$\bf{\underline{\underline{Given:}}}$

• Car takes 2 hour to reach @speed of 60 km/hr

$\bf{\underline{\underline{To\:Find:}}}$

• How long it would take to reach @speed of 80 km/hr

$\bf{\underline{\underline{Solution:}}}$

If speed will increase then time will decrease. Hence,It is case of Inverse Variation.

Let the time taken be x hours

$\bf{\underline{\underline{According\:To\:Question:}}}$

$\sf \dfrac{Time}{Speed} | \dfrac{2}{60} | \dfrac{x}{80}|$

$\implies \sf \: 2 \times 60 = x \times 80$

$\implies \sf \: x = \dfrac{60 \times 2}{80}$

$\implies \sf \: x = \cancel\dfrac{120}{80}$

$\sf \: x = 1.5 \: hours$

Hence, Time taken = 1 hour 30 min