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If the difference between the circumference and the radius of a circle is 37 cm, then using`22/7`, the circumference (in cm) of the circle is:

#### Options

(A) 154

(B) 44

(C) 14

(D) 7

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#### Solution

Difference between circumference and radius of the circle = 37 cm

Let *r* be the radius of the circle.

`therefore 2 pi r-r=37 cm`

`rArr r(2pi-1)=37cm`

`rArr r(2xx22/7-1)=37 cm`

`rArrrxx37/7=37cm`

`rArrr=7cm`

∴ Circumference of the circle = `2pir=2xx22/7xx7cm=44cm`

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