Question

a man covers 5 km in 1 hour by walking next 20 km in 2 hours by boat and the the remaining hundred kilometre in 2 hours by train was his average speed?​

Answer 1

Answer:

Ans- Avarage speed- 25Km

Answer 2

Answer:

25 km/h

Explanation:

As per the provided information in the given question, it has been stated that a man covers 5 km in 1 hour by walking next 20 km in 2 hours by boat and the the remaining 100 km in 2 hours by train. We've been asked to calculate the average speed.

We have,

• He covers 5 km in 1 hour.
• Then, he covers 20 km in 2 hours by boat.
• And remaining 100 km in 2 hours by train.

― Average speed of a body is defined as total distance covered divided by total time taken. In order to calculate the average speed of the body, we need to calculate the total distance covered and total time taken first.

$\underline {\large \sf { Total \; distance \; covered \; :}} \;$

Total distance covered will be the sum of the distances covered by him in the different parts. Let the total distance be S.

$\longrightarrow \sf{\quad { S = (5 + 20 + 100)\; km }}$

$\longrightarrow\quad \boxed{\sf{ { S = 125 \; km }}}$

$\underline {\large \sf { Total \; time \; taken \; :}} \;$

Total time taken will be the sum of the time taken covered by him to cover the distances of thr different parts. Let the total time taken be T.

$\longrightarrow \sf{\quad { T = (1 + 2 + 2)\; h }}$

$\longrightarrow \quad \boxed{\sf{{ T = 5 \; h }}}$

Now, as we know that,

$\longrightarrow \boxed{ \quad { \textbf{\textsf{Speed}}_{\textbf{\textsf{(Avg)}}} = \dfrac{\textbf{\textsf{Distance}}_{\textbf{\textsf{(Total)}}}}{\textbf{\textsf{Time}}_\textbf{\textsf{(Total)}}} }}$

Substitute the values in the formula,

$\longrightarrow \sf{\quad {V_{(avg)} = \dfrac{S}{T} }}$

$\longrightarrow \sf{\quad {V_{(avg)} = \cancel{\dfrac{125 \; km}{5 \; km} }}}$

$\longrightarrow \quad \underline{ \boxed{ \textbf{\textsf{V}}_{\textbf{\textsf{(avg)}}} = \textbf{\textsf{25 \; km}} \; \textbf{\textsf{h}}^{\textbf{\textsf{-1}}} }}$

$\underline{ \qquad\qquad\qquad\qquad\qquad\qquad\qquad\qquad}$

Therefore,

⠀⠀★ Average speed = 25 km/h