A piece of 1 inch from bar of 7 inch is to be given to a worker daily up to 7 days as payment and condition is that he can cut the bar only two times.

• The trick is not to try and how to cut in such a way to make 7 equal pieces but rather to make transactions with the worker. Make two cuts on the bar such that you have the following sizes of bars.
  
  1/7, 2/7 and 4/7. For convenience sake, I would just refer to the bars as 1, 2 and 4.
  
  At the end of Day 1: Give Bar 1 (You- 2 and 4, Worker- 1)
  
  At the end of Day 2: Give Bar 2, Take back Bar 1 (You- 1 and 4, Worker- 2)
  
  At the end of Day 3: Give Bar 1 (You- 4, Worker- 1 and 2)
  
  At the end of Day 4: Give Bar 4, Take back Bar 1 and Bar 2 (You- 1 and 2, Worker- 4)
  
  At the end of Day 5: Give Bar 1 (You- 2, Worker- 1 and 4)
  
  At the end of Day 6: Give Bar 2, Take back Bar 1 (You- 1, Worker- 2 and 4)
  
  At the end of Day 7: Give Bar 1 (You- Empty, Worker- 1, 2 and 4)
  
  That should take care of everything.
• 8 years agoHelpfull: Yes(0) No(0)