Question

The length of a rectangular plot of ground is 5 times its breadth and its area is 5 hectares. How long will a man take to walk around it at the rate of 1.5 km/hr

Answer 1

Answer:

Step-by-step explanation:

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