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Question
The curved surface area of a right circular cone of radius 11.3 cm is 710 cm2. What is the slant height of the cone ?
Solution
Curved surface area = 710 cm2
Radius (r) of base = 11.3 cm
Let Slant height be l .
`therefore pirl = 710`
⇒ `22/7 xx 11.3 xx l = 710`
⇒ `l = (710 xx 7)/(11.3 xx 22)`
⇒ l = 19.99 cm = 20cm
The slant height is 20 cm.
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