minimum no of weight required to wait from 1-40 kg..

• The answer is 4 weights -- 1kg, 3kg, 9kg and 27 kg.
  
  Explanation:
  For 1 kg - Put 1 kg on one side of the plate
  For 2 kg - Put 3 kg on one side of the plate, 1 kg on the other side of the plate
  For 3 kg - Put 3kg on one side of the plate
  For 4 kg - Put 3kg and 1 kg on one side of the plate
  For 5 kg - Put 9kg on one side of the plate, and put 1kg and 3kg on the other side of the plate
  ...
  Likewise,
  For 40 kg - Put 1kg, 3kg, 9kg, 27kg on one side of the plate
  
• 11 years agoHelpfull: Yes(34) No(4)
• case 1: answer is 4
  if weight is allowed to keep both sides of weighing machine then required weight will be 4 like this 1kg,3kg,9kg,27kg.
  case 2: answer is 6
  if weight is allowed to keep only one side of weighing machine then required weight will be 6 like this 1kg,2kg,4kg,8kg,16kg,32kg
• 11 years agoHelpfull: Yes(7) No(1)
• 6
  on taking the binary of 40, we will get 6 steps
• 11 years agoHelpfull: Yes(4) No(3)
• Answer is 4. The weights required would be 1,3,9,27.
  
  For each weight, there are three things you can do: put it on the left
  pan, the right pan, or not on the balance at all.
  
  So, if you have n weights, there are 3^n things you can do with them.
  
  One of those things is not putting any weights on the scale, which is
  good if you want to weigh a 0-pound object, so really there are only
  3^n - 1 arrangements.
  
  Then, for each arrangement there's also its mirror image (where all
  the weights are switched to the opposite pan of the scale), so there
  are at MOST (3^n - 1)/2 arrangements of n weights.
  
  That's enough to prove that 4 weights can weigh at most 40 different
  things ... 40 is really the upper limit for 4 weights.
• 11 years agoHelpfull: Yes(4) No(0)
• weights of 1kg,2kg,5kg,10kg and 30 kg will be sufficient to weigh 1 to 40 kg. So minimum no. of weights will be 5.
  In the solution given below with 4 weights you cannot weigh 16 kg.
• 11 years agoHelpfull: Yes(1) No(1)
• @AJV,ashima gupta- i got it that it can be measured by 1,3,9,27.. but how did u got these values??????
• 11 years agoHelpfull: Yes(0) No(0)