Question

The inner circumference of a circular
acupressure track is 115 m and width of
the track is 5 m. Find the cost of putting
up a fence along the outer circle of the
track at the rate of 120 m.​

Answer 1

Answer:

115 m inner circumference(given)

and width 5m(given)

let inner circle radius be r1

circumference of small circle=2πr

115=2×22/7 ×r1

115/2 ×7/22=r1

r1=18.29(approx)

let radius of bigger circle=(r2)

which is r1+5

18.29+5

(r2)=23.29

so new circumference=2π(r2)

2×22/7×23.29

146.39m

14639/100

cost=rate×length

cost=120×2329/100

12×2329/10

2794.8 Rs

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