The radius of the base and height of a right circular cone are in the ratio 8 : 15. Find the slant height of the cone of its volume is cm3.
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Correct answer: A
Explanation
The correct answer is option 1 i.e 17 cm.
Radius : Height = 8 : 15
Volume = 1005 5/7 = 7040/7 cm³
Volume of cone = 1/3 × π × r² × h
Let r = 8k, h = 15k
Volume = 320πk³ = 7040/7
Using π = 22/7 → 320 × 22/7 × k³ = 7040/7 ⇒ 7040k³ = 7040 ⇒ k = 1
So r = 8, h = 15
Slant height = √(r² + h²) = √(64 + 225) = √289 = 17