Question

The width of a circular track is 2 meters. If the radius of the outer circle is 6 meters, find the area of the track in pi terms

Answer 1

Answer:

Let radius of the outer circle = R m

and radius of the inner circle = r m

Now, 2πR=220

⇒2×

7

22

×R=220

∴R=

2×220

220×7

=35m

∴ Width of the track =7m

r=35−7=28m

Area of the circular track =π(R

2

−r

2

)

=

7

22

(35

2

−28

2

)

=

7

22

×(35+28)(35−28)

=

7

22

×63×7=1386m

2

∵ Rate of levelling the track=Rs.0.50/m

2

∴ Cost of levelling the track

=Rs.0.50×1386=Rs.693.

Answer 2

Answer:

That's your answer little one.