the area of a rectangular field is 3584m sq and its lenght is 64m. A boy runs around the field at the rate of 6 km/h. how long will he take to go 5 times around it?

Area of rectangular field = 3584 ${\mathrm{m}}^{2}$

So breadth of rectangular field = $\frac{3584}{64}=56$ m

Then, Perimeter of rectangular field = $2\left(64+56\right)=240\mathrm{m}$

Now a boy is running 5 times around the field. So total distance covered by a boy = $240\times 5=1200$ m

Speed = 6km/h = $\frac{6\times 1000}{60\times 60}=\frac{5}{3}$m/s

So time taken by boy to cover the total distance = $\frac{1200}{{\displaystyle \frac{5}{3}}}=\frac{1200\times 3}{5}=720$

therefore time taken by boy is 720 seconds.

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