Question

The area enclosed by a circular plot is 616 sq. m. Find the diameter of the plot. Also find the cost of fencing it at the rate of 7 per metre.​

Answer 1

Answer: d=28m cost= rs 616

Step-by-step explanation:

solution

given

area=616 sq.m.

we know that

area= pi*r^2

616= 22/7 * r^2

616*7/22= r^2

196=r^2

r= 14m

now,

d=2r

d= 2*r

therefore d= 28 m

1m= rs 7

perimeter of circle= 2*pi*r

2*22/7*14

p= 88 cm

hence,

cost of fencing at rate of 7 per m= 7*88

rs 616

Answer 2

Given: Area of the circular plot is 616 sq. m.

To find: Diameter of the plot

The area of a circle is π r2

Therefore, π r2 = 616 sq. m.

R sq.= 616/3.14

= 196.17

= √196.17= 14.006

Diameter= 28.1

Cost of fencing,

Perimeter of a circle= 2πr

2πr = 87.92

Cost of fencing per meter=7

Cost of fencing 87.92 m= 7* 87.92

= 615.48