There are 6561 balls out of them 1 is heavy. Find the min. no. of times the balls have to be weighedfor finding out the heavy ball.

• 6561 if u notice is 3^8...n can be divided by 3(prime factor) only...we keep on dividing it into sets of 3 and in 1 weighing itself you can determine which set is heavy. Divide that set into further 3 lots...keep doing that..
  6561
  2187 2187 2187 1st weighing
  729 729 729
  243 243 243
  81 81 81
  27 27 27
  9 9 9
  3 3 3
  1 1 1
  ANswer is 8 attempts
  
• 14 years agoHelpfull: Yes(20) No(3)
• ans is 8.(because 3^8=6561)
  coz divide all the balls in group of 3...
  out of 3 ball min no of times to find the heavy is 1.
  hence the solution....
• 14 years agoHelpfull: Yes(14) No(9)
• 8 times
• 14 years agoHelpfull: Yes(5) No(10)
• bt 6561 is perfect square of 81 ..so we can seperate the balls into 81 boxes each containing 81 balls. So nxt tym we will have only 81 balls to measure, then we can divide them again into 81 or may b 9..in this way no of times required will be less than 8...plz clear me if im worng:)
• 9 years agoHelpfull: Yes(1) No(0)