Question

)
1- The inner circumference of a circular track is 220m
the track is 7m width everywhere calculate the
cost of putting up a fence along along the outer circle at
the rate of Rs 2 per meter
,​

Answer 1

${\textsf{\textbf{\underline{Given :-}}}}$

The inner circumference of a circular track is 220m  the track is 7m in width everywhere

${\textsf{\textbf{\underline{To\;Find :-}}}}$

Cost of fencing

${\textsf{\textbf{\underline{Solution :-}}}}$

We know that

C = 2πr

⇒ 220 = 2 × 22/7 × r

⇒ 220 = 44/7 × r

⇒ 220 × 7/44 = r

⇒ 5 × 7 = r

⇒ 35 = r

Now

Outer Radius = Inner radius + Width

Outer radius = 35 + 7

Outer radius = 42 cm

Outer circumference = 2πr'

⇒ C = 2 × 22/7 × 42

⇒ C = 44/7 × 42

⇒ C = 44 × 6

⇒ C = 264

Cost = Circumference × Rate

Cost = 264 × 2

Cost = Rs. 528

Answer 2

➡️ ANSWER

☆ Given,

The inner circumference of a circular track is 220m  the track is 7m in width everywhere.

☆ To Find?

● Cost of fencing

☆ Solution:-

We know that

C = 2πr

⇒ 220 = 2 × 22/7 × r

⇒ 220 = 44/7 × r

⇒ 220 × 7/44 = r

⇒ 5 × 7 = r

⇒ 35 = r

Now

Outer Radius = Inner radius + Width

Outer radius = 35 + 7

Outer radius = 42 cm

Outer circumference = 2πr'

⇒ C = 2 × 22/7 × 42

⇒ C = 44/7 × 42

⇒ C = 44 × 6

⇒ C = 264

Cost = Circumference × Rate

Cost = 264 × 2

Cost = Rs. 528