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The radius and slant height of a cone are In the ratio of 4 : 7. If its curved surface area is 792 cm2, find its radius. (Use it ЁЭЬЛ = 22/7).
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Given that,
Curved surface area=`pirl=792`
Let the radius `(r)=4x `
Height `(h)=7x `
Now, CSA=792
`22/7xx"4x"xx7x=792`
⇒ `88x^2=792`
⇒` x^2=792/88=9`
⇒ `x=3`
∴ Radius =`4x=4xx3=12cm`
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