Question

Length of rectangular plot is 3 times its breadth having area 3 hectare . A man walks on its perimeter at 4 km/hr . Find the time required ?

Answer 1

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Answer 2

1 hactare = 10000 square meters

Area of the field = 3 × 10000 = 30000 square meters

Let the breadth be x.

The length = 3x

Area = 3x × x = 3x^2

3x^2 = 30000

x^2 = 30000/3

x^2 = 10000

x = 100

The length = 100 × 3 = 300 m

Convert the dimensions to km.

Length = 300/1000 = 0.3 km

Width = 100/1000 = 0.1 km

Perimeter  = (0.1 + 0.3) 2 = 0.8km

Time = Distance / speed

Time = 0.8/4 = 0.2 hrs

0.2 × 60 = 12 minutes