Question

l need answer of questions 21 solve it step by step​

Answer 1

Answer:

At draw a circle (circular field) and then draw a circle around the circle ( path)

Then

Let radius of inner circle be r

And radius of outer circle be R

So r = 140 m

And R = 140+7 = 147 m

Then

Area of inner circle = π r^2 = 22/7×140×140 =22 × 20 × 140 =61600 m square

And

Area of outer circle= π R^2 = 22/7 × 147 × 147 = 22 × 21 × 147 = 67914 m square

Therefore

Area of path = Area of outer circle - Area of inner circle = 67914 - 61600 =6314 m square

Now

Cost of levelling it at ₹5 per square metre = 6314 × 5 = ₹31570