Question

The area of a rectangular field is 3584 m² and its length is 64 m. A boy runs around the field at the rate of 6 km/h. How long will he take to go 5 times around it?

Answer 1

Area of the rectangular field = 3584 m²
Length of the rectangular field = 64 m
Breadth of the rectangular field = $\left(\frac{\mathrm{Area}}{\mathrm{Length}}\right)$ = $\left(\frac{3584}{64}\right)$ m = 56 m
Perimeter of the rectangular field = 2 (length + breadth)
= 2(64+ 56) m = (2 $\times$ 120) m = 240 m
Distance covered by the boy = 5 $\times$ Perimeter of the rectangular field
= 5 $\times$ 240 = 1200 m

The boy walks at the rate of 6 km/hr.
or
Rate = $\left(\frac{6\times 1000}{60}\right)$ m/min = 100 m/min.

∴ Required time to cover a distance of 1200 m = $\left(\frac{1200}{100}\right)$ min = 12 min
Hence, the boy will take 12 minutes to go five times around the field.