Make 1000

Use this strange calculator to make a total of 1000. Find as many different ways of doing it as possible.

You can earn a Transum Trophy for finding 10 or more different ways.

For this exercise, the order of the calculation does matter, i.e. adding three numbers in a different order counts as a different calculation.

Here are your solutions

 

Strategies for Solving the Challenge

  1. Check the Ones (Units) Digit: Adding the units digits of the three numbers can give a quick indication of whether they can sum to a number ending in zero.
  2. Permutations: For each triplet of numbers found, remember that there are six different permutations (ways or ordering) of those three numbers (if they are all different).
  3. Binary Search Technique: Sort the numbers in ascending order. Start by picking the smallest number and use a binary search approach (methodical method) to find two other numbers whose sum with the first number equals 1000.
  4. Use of a Spreadsheet: Enter the numbers into a spreadsheet and use formulas to quickly test combinations.
  5. Grouping and Averaging: Group numbers into approximate ranges (e.g., 200-300, 300-400, etc.). This can make it easier to identify potential combinations that might work together.
  6. Elimination Process: As you find combinations that work, remove those numbers from the pool to reduce the number of options for subsequent combinations.
  7. Trial and Error with Record Keeping: Keep a record of all tried combinations. This prevents repeating the same calculations and helps in systematically covering all possible combinations.
  8. Mathematical Tools: Utilize mathematical tools or programming to automate the search for combinations. Basic programming skills can be handy here to write a simple script that tests all combinations.

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Tran Tunnels

Tran Tunnels

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