Question

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

Answer 1

Step 1: Given

Speeds,

$$\begin{gathered} v_1=60km/hr \\ {v}_2=80km/hr \end{gathered}$$

Time taken, $t_1=2hours$

Step 2: Formula used

$Speed=\frac{Dis\tan ce}{Time}$

Step 3: Determine the distance using the known velocity and time

$$\begin{gathered} Speed=\frac{Dis\tan ce}{Time} \\ {v}_1=\frac{d}{t_1} \\ d=60\times 2 \\ =120km \end{gathered}$$

Step 4: Determine the time taken with the new speed

As the destination is the same, the distance will remain the same.

$$\begin{gathered} Speed=\frac{Dis\tan ce}{Time} \\ {v}_2=\frac{d}{t_2} \\ {t}_2=\frac{120}{80} \\ =1.5hours \end{gathered}$$

Therefore, the car takes $1.5hours$ to reach the destination if it travels at the speed of $80km/hr$.