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DIY Challenge 1: Cut the 10 unit gold bar

We have a gold bar of length 10. You have pay a person for 10 days.

At the end of 1st day, the person should have 1 unit.
At the end of 2nd day, the person should have 2 units.
……
At the end of 10th day, the person should have 10 units.

  • We are allowed to take back the some units which you gave on earlier days
  • At the end of any day, the total must be correct (coins equal to the day number)

Which all positions will you make the cuts on the gold bar? Maximum cuts allowed is 4.

Challenge: Can you do it in just 3 cuts?

What students worked out7

  • Student 3

    Day Give Take back
    1 1 –
    2 2,3 1
    3 1
    4 4,5,6,7 1,2,3
    5 1
    6 2,3 1
    7 1
    8 8,9,10 2,3
    9 2,3 1
    10 1

    this is my finding Sir
    we need three cuts so that we can cut bar in to pieces of 1,2,3,4 bars
    so lines of cut can vary accordingly

    for example here…A,C and G
    Similarly it could be ACF, ADF, AEH, vice versa IGC, IFD, IFB etc

  • Student 3

    Earlier content got distorted

  • Student 2

    cut on A/C/F
    DAY 1 – GIVE 1
    DAY 2 – TAKE BACK 1 GIVE 2/3
    DAY 3 – TAKE BACK 2/3 GIVE 4/5/6
    DAY 4 – GIVE 1
    DAY 5 – TAKE BACK 1/4/5/6 GIVE 1/7/8/9/10
    DAY 6 – TAKE BACK 1 GIVE 2/3
    DAY 7 – GIVE 1
    DAY 8 – TAKE BACK 1/2/3/7/8/9/10 GIVE 1/4/5/6/7/8/9/10
    DAY 9 – TAKE BACK 1/4/5/6/7/8/9/10 GIVE 2/3/4/5/6/7/8/9/10
    DAY 10 – GIVE 1
    THERE ARE MANY MORE WAYS TO DO THIS THIS IS ONE OF THEM

  • Student 2

    WE DONT NEED 4 CUTS

  • Student 1

    Day1: Give 1 and take back
    Day2: Give 2 3 and take back
    Day3: Give 4 5 6 and take back
    Day4: Give 7 8 9 10 and take back
    Day5: Give 7 8 9 10 1 and take back
    Day6: Give 7 8 9 10 2 3 and take back
    Day7: Give 7 8 9 10 4 5 6 and take back
    Day8: Give 7 8 9 10 4 5 6 1 and take back
    Day9: Give 7 8 9 10 4 5 6 2 3 and take back
    Day10: Give all

    • Student 1

      This is the image

  • Student 4

    cut on A, C, F.
    1 day: give 1
    2 day: take 1 give 23
    3 day: give 1
    4 day:give 4567 take back 123
    5 day: give 1
    6 day: give 23 take 1
    7 day: give 1
    8 day: take 1 give 89
    9 day: give 1
    10 day: give 10