Three unit circles are enclosed in a large circle such that they touches each other. Find the area of larger circle.(use π=3.14)

• centres of 3 circles form eq triangle of side 2
  join centre of big circle to any other centre & draw perpendicular
  
  cos 30 = 1 / x => x = 2/ root(3) where, x = distance b/n centres of smaller & bigger circle.
  
  R = (1 + 2/root3) = 2.15
  
  Area of larger circle = 3.14 * (2.15)^2 = 14.57 sq unit
• 9 years agoHelpfull: Yes(23) No(1)
• By joining centers of 3 unit circles we will get an equilateral triangle of length 2 unit. We have to find the length of the orange line.
  And center of the equilateral triangle will be the center of the big circle.
  So radius of the big circle will be = (1 + Circum radius of the equilateral triagle)
  Circum radius of equilateral triangle = 23×3√2×2=23√
  Area of big circle will be =πr2=3.14×(1+23√)2 = 3.14×(1+43√+43)
  =3.14×(1+43√+43) = 3.14×(73+43√)
  =3.14×(7+43√3)
• 9 years agoHelpfull: Yes(2) No(4)
• ans is 12.56
  
• 9 years agoHelpfull: Yes(1) No(5)
• ans is 28.26
• 9 years agoHelpfull: Yes(1) No(2)
• unit circle mean having radius 1 .so 12.56 is right ans. if any1 have another soln then explain othrwise jst folow it.
  
• 9 years agoHelpfull: Yes(1) No(2)
• Since the smaller circle have radius 0ne therefore when we join the center of all three small circle we will get equilateral triangle. now the center of equilateral triangle can be find by using formula
• 9 years agoHelpfull: Yes(1) No(3)
• which formula plz explain @ sandeep kumar
• 9 years agoHelpfull: Yes(1) No(2)
• 3 circles are touching together also touch big circle then if the radius of unit circle is r ,then the radius of enclosed circle is 2r .
  the area of the enclosed circle is = 3.14*(2r^2)
  =3.14*4*r*r
  =12.56*r*r
• 9 years agoHelpfull: Yes(0) No(3)
• The ans is = 14.57 cm square
• 9 years agoHelpfull: Yes(0) No(2)
• ans = 9*3.14-3*3.14=6*3.14=18.84
• 9 years agoHelpfull: Yes(0) No(2)
• Which is correct answer??
• 9 years agoHelpfull: Yes(0) No(0)