Question

A car travels 30 km in half an hour. what is the speed of the car?​

Answer 1

Step-by-step explanation:

If a car covers 30 km in half an hour, what is its speed?

In most cars, unit of speed on speedometer is km/h means it tells how many kilometers car will cover in one hour. Equation for speed in km/h is:

Speed (in km/h) = Distance (in km) / time (in hour)

Now the given information is that a car covers some distance in half an hour. So, to get speed of car following two steps are performed:

Convert the time in minutes i.e.

Speed (in km/h) = Distance (30 km) / time (30 min)

As we know that an hour has 60 min so we will multiply time with two. Now math has a rule which goes something like this. Whatever action you performed on an expression, its counter action should also be performed. So we will multiply time with two and at the same time divide it by two. We get the following:

Speed (in km/h) = Distance (in km) / time ((2/2) x 30 min)

here multiply time with two to get 60 min which will give us one hour and (1/2) will act as divisor of distance. Equation becomes

Speed (in km/h) = Distance (30 km) /(1/2) time (60 min or 1 hour)

If we write it simply then it becomes something like this.

Speed = 30 / (1/2)

Performing the calculation using calculator we get:

Speed = 60 km/h

Answer 2

Given: Distance travelled by the car = 30 km

           Time taken = 30 minutes (half hour)

To find: Speed of the car

Solution: According to the given question,

Distance travelled by the car in 30 minutes = 30 km

Distance = 30 km Time = 30 minutes or 0.5 hour

Using Speed formula:

.: Speed = $\frac{Distance}{Time}$

Speed of the car = Distance covered by the car (30 km) / Time taken by it to cover that distance (0.5 hour)

                             = $\frac{30}{0.5}$ = 60

Hence, speed to the car is 60 km/h

The car is travelling at the speed of 60 km/h to cover the distance of 30 km in half hour.