Question

Avinash travelled 42 km 365 m by bus, 12 km 460 m by car and walked 640 m. How many kilometers did he travel altogether?

Answer 1

Hint: Add the distance given in meters separately and distance given in kilometers separately. If the added distance in meters exceeds 1000 then change this 1000 m into 1 km, because we know that 1 km = 1000 m. Now, to change the remaining distance (which is in meters) in km, we have to divide it by 1000. Write the overall distance as a decimal representation.

Complete step-by-step answer:
We know that the sum of two quantities is possible only when their dimensions or unit are the same.
In the above question, we have to add distances covered by Avinash. We must add the distances given in kilometers together and the distances given in meters together. We cannot add the distance given in meters with the distance given in kilometers directly because their dimensions are not the same.
Now, it is given that Avinash travelled 42 km 365 m by bus, 12 km 460 m by car and walked 640 m. we have to find the total distance travelled by Avinash.
Distance travelled by Avinash in meters = (365 + 460 + 640) = 1465. This can be written as:
1465 m = 1000 m + 465 m
We know that, 1 km = 1000 m. So, 1465 m = 1000 m + 465 m = 1 km 465 m.
Now, distance travelled by Avinash in kilometers = (42 + 12) = 54.
Therefore, the total distance travelled by Avinash is 54 km + 1 km + 465 m = 55 km 465 m.
To change 465 m into kilometer, we have to divide 465 by 1000, since, $1\text{ m}=\dfrac{1}{1000}\text{ km}$. Therefore,
$\begin{align}
  & 465\text{ m}=\dfrac{465}{1000}\text{ km} \\
 & \Rightarrow 465\text{ m}=0.465\text{ km} \\
\end{align}$
Hence, total distance covered by Avinash = 55.465 km.

Note: Always remember that the addition or subtraction of two quantities takes place when their units or dimensions are the same. We can also solve this question by changing the distances given in meters into kilometers directly in the first step only. This step will give us three decimal numbers which can be easily added.