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A joker’s cap is in the form of a right circular cone of base radius 3 dm and height 4 dm. Find the area of the sheet required to make 35 such caps.
Asked by Topperlearning User | 17 Oct, 2017, 09:16: AM
answered-by-expert Expert Answer

Given: Radius (r) = 3 dm, height (h) = 4 dm. Let slant height = l     

begin mathsize 12px style l squared space equals space straight r squared space plus space straight h squared l space equals space square root of space straight r squared space plus space straight h squared end root l space equals space square root of 3 squared space plus space 4 squared end root l italic space equals space 5 space dm Lateral space surface space area space equals space πr l equals 22 over 7 cross times 3 cross times 5 equals fraction numerator 330 over denominator 7 space dm squared end fraction Aera space of space sheet space required space to space make space 35 space such space caps space equals space 35 cross times 330 over 7 space equals space 1650 space dm squared end stylebegin mathsize 12px style l squared space equals space straight r squared space plus space straight h squared l space equals space square root of space straight r squared space plus space straight h squared end root l space equals space square root of 3 squared space plus space 4 squared end root l italic space equals space 5 space dm Lateral space surface space area space equals space πr l equals 22 over 7 cross times 3 cross times 5 equals fraction numerator 330 over denominator 7 space dm squared end fraction Aera space of space sheet space required space to space make space 35 space such space caps space equals space 35 cross times 330 over 7 space equals space 1650 space dm squared end style

  

 

 

Answered by | 17 Oct, 2017, 11:16: AM

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