Question

Find the speed of a car, if it can travel a distance of $217$ kilometers in $3$ hours $30$ minute.

Answer 1

Hint: Car travels a distance of $217$ kilometers in $3$ hours and $30$ minute. To find speed we use formula $speed = \dfrac{{dis\tan ce}}{{time}}$

Complete step-by-step answer:
Given,
Distance at which car was travelling $ = 217km$
Time taken to cover given distance $ = 3$ hours $30$ minutes
Time is given in hours and minutes. Convert it into minutes
Therefore,
Time $ = 3 \times 60 + 30 = 180 + 30 = 210$ minutes
Time cover to travel given distance can be written as $ = \dfrac{{210}}{{60}}$hours
Step2: Given time and distance using this find speed of the car.
We know that speed is calculated using distance i.e. distance traveled per hour.
Speed $ = \dfrac{{dis\tan ce}}{{time}}$
Putting values for distance and time we will obtain the speed of the car at which it is traveling.
Distance $ = 217km$
Time $ = \dfrac{{210}}{{60}}$hours
Speed $ = \dfrac{{217}}{{\dfrac{{210}}{{60}}}}$
Simplifying we get,
Speed$ = 217 \times \dfrac{{60}}{{210}}$
Solve,
Speed$ = \dfrac{{13020}}{{210}}$
Speed$ = 62km/hour$
Therefore, the speed of the car is $62km/hour$ at which it was travelling.

Note: In this type of questions it is required to change time in the same unit i.e. minute into hour or hour into minute in this way it will be convenient to obtain required results of given data. In this problem the time was in hours and minutes so required to change in minutes in order to obtain a result .Then use the formula of speed to calculate at which speed the car was travelling as value for time and distance is provided. Similarly, if the distance is in meters we need to change it in kilometers. All values should be in the same units.