Advertisement Remove all ads

The Outer Circumference of a Circular Race Track is 528m. the Track is Everywhere 14m Wide. Calculate the Cost of Leveling the Track at Rate of 50 Paise per Square Metre. - Mathematics

Sum

The outer circumference of a circular race track is 528m. The track is everywhere 14m
wide. Calculate the cost of leveling the track at rate of 50 paise per square metre.

Advertisement Remove all ads

Solution

Let inner radius = r      width(d) = 14m

Outer radius = R

Outer circumference of track = 2 𝜋𝑟

∴ 2 𝜋𝑟 = 528

`2 ×22/7× R = 528 ⇒ R =528×7/2×22= 84 m`

Inner radius r = R – d = 84 – 14 = 70m

Area of track = (area of outer circle) – (area of inner circles)

= 𝜋𝑅2 − 𝜋𝑟2

`= pi(R^2 − r^2) =22/7(84^2 − 70^2)`

`=22/7(84 + 70)(84 − 70) =22/7× 154 × 14`

= 6776 𝑚2

Cost of leveling 𝑚2 = 𝑅𝑠. 0.50

Total cost of leveling track = 6776 ×`1/2`= 𝑅𝑠. 3388

 

 

 

 

  Is there an error in this question or solution?
Advertisement Remove all ads
Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×