Question

a rectangular field is 90m by 70m.A man walks round it at the rate of 4 km per hour .What time will he take in make 5 rounds of the field

Answer 1

Given: A rectangular field is 90m by 70m and a man walks around it at the rate of 4km/h.

Need to find: Time he'll take to make 5 rounds of the field.

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$\underline{\bf{\dag\;}\frak{As\;we\;know\;that:}}$

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$\star\;\boxed{\pink{\sf{Perimeter\;_{(rectangle)}=2(Length+Breadth)}}}$

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Therefore,

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$\begin{gathered}:\implies\sf{2(90+70)}\\\\\\\\:\implies\sf{180+140}\\\\\\\\:\implies\underline{\boxed{\frak{\purple{320\;m}}}}\;\bigstar\end{gathered}$

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$\qquad\qquad\footnotesize{\underline{\bf{\dag\;}\frak{Distance\;covered\;in\;5\;rounds:}}}$

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$\begin{gathered}:\implies\sf{(5\times 320)\;m}\\\\\\\\:\implies\sf{1600\;m}\\\\\\\\:\implies\sf{\dfrac{1600}{1000}}\\\\\\\\:\implies\underline{\boxed{\frak{\pink{1.6\;km}}}}\;\bigstar\end{gathered}$

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$\qquad\qquad\footnotesize{\underline{\bf{\dag\;}\frak{Time\;taken\;in\;making\;5\;rounds:}}}$

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$\begin{gathered}:\implies\sf{Time=\dfrac{Distance}{Speed}}\\\\\\\\:\implies\sf{\dfrac{1.6\;km}{4\;h}}\\\\\\\\:\implies\sf{0.4\;hours}\\\\\\\\:\implies\sf{0.4\times 60}\\\\\\\\:\implies\underline{\boxed{\frak{\purple{24\;minutes}}}}\;\bigstar\end{gathered}$

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$\therefore\;{\underline{\sf{Hence,\;time\;taken\;to\;make\;5\;rounds\;is\;{\textsf{\textbf{24\;minutes}}}}.}}$⠀⠀⠀

Answer 2

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✰ GiveN :-

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• A rectangular field is 90m by 70m.
• A men walks round it at the rate of 4 km per hour.

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✰ To FinD :-

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• what time will he take in make 5 rounds of the field.

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✰ SolutioN :-

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❒ Perimeter of the rectangle ↴

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Formula used :-

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$\begin{gathered}{ \red{ \underline{ \boxed{ \bf{Perimeter = 2(l + b)}}}}} \end{gathered}$

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✾ Where ~

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l = length

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b = breadth

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$\quad : \implies \sf{Perimeter = 2(90 + 70)}$

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$\quad : \implies \sf{Perimeter = 2(160)}$

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$\quad : \implies \sf{Perimeter = 320}$

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$\begin{gathered}{ \blue{ \underline{ \boxed{ \sf{∴ Perimeter \: of \: the \: rectangle \: is \: 320m}}}}} \end{gathered}$

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❒ Distance covered in 5 rounds ↴

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$\qquad : \implies\sf {5 \times 320m}$

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$\qquad : \implies\sf{1600m}$

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$\qquad : \implies{ \dfrac{1600}{1000} }$

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$\qquad : \implies \sf{1.6 km}$

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$\begin{gathered}{ \blue{ \underline{ \boxed{ \sf{∴ Distance \: covered \: in \: 5 \: rounds \: = 1.6km}}}}} \end{gathered}$

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❒ Time taken in making 5 rounds↴

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Formula used :-

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$\begin{gathered}{ \blue{ \underline{ \boxed{ \sf{Time = \frac{ Distance}{speed} }}}}} \end{gathered}$

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$\qquad : \implies \sf{Time = \cancel\dfrac{1.6}{4} }$

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$\qquad : \implies \sf{Time = 0.4 \times 60}$

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$\qquad : \implies \sf{Time =24 \: mins }$

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$\begin{gathered}{ \blue{ \underline{ \boxed{ \sf{∴ Time \: taken \: in \: 5 \: rounds \: = 24 \: mins}}}}} \end{gathered}$

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