Question

A car takes 7vhoues to cover a certain distance at the speed of 48 khm/hr if the speed is decreasedby 20 km/hr . How much time will it take to cover the same distance

Answer 1

Given, original speed of car = 48 km /h

original time = 7 hrs

since we know, distance = speed × time

distance = 48 × 7 = 336 km

since , the speed is decreased by 20km /hr

then , find new speed of car :

new speed = original speed - decrease in the speed

new speed = 48 - 20 = 28 km /hr

since, given that the distance covered by car is same , then find new time :

new time = distance / new speed

new time = 336 / 28 = 12 hrs

therefore, the car will take 12 hours to cover the same .

Your Answer : required time = 12 hrs

Answer 2

Hey there!

Data provided to us in this query are as follows,

Time taken for the car to cover a definite distance = 7 hours.

Speed acquired by the car while completing that distance = 48 km/hr.

Distance of the car by which it traveled by above speed and time = d.

By taking the unknown distance as a variable to find the value as "d".

As per the basic formula to calculate distance, here,

$\textbf{Total Distance covered by the car}$

$\textbf{= Speed of the car}$ $\bf{\times}$ $\textbf{Time Taken by the car}$

$\bf{d = 48 \: km\hr \times 7 \: hours}$

$\bf{d = 336 \quad \frac{km\hr}{hours}}$

$\bf{d = 336 \: km}$

Since, the speed is decreased up to 20 km/hr the speed will be subtracted from original distance that is "48 km/hr".

$\bf{DS = 48 \: km\hr - 20 \: km\hr}$

$\bf{DS = 28 \: km\hr}$

Now, applying the formula for time to uncover the value taken to cover that distance that is,

$\textbf{Time Taken =}$ $\bf{\frac{Distance \: Of \: the \: Car}{Speed \: of \: the \: Car}}$

$\bf{T = \dfrac{336 \: km}{28 \: km\hr}}$

$\boxed{\underline{\bf{T = 12 \: hrs}}}$

Hence, it'll take a total time of "12 hours" to complete that distance of the car.

Hope this helps you and solves the doubts for calculating the time taken by set variables!!!!