What is the original number?

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Question from Yueh, a student:

A five digit number is written on a blackboard. Ron erases one of the
digits and adds a newly constructed number to the original one. The result
is 41751. What is the original number?

Yueh,

I think you mean "... adds THE newly constructed number to the original one''.

- The first clue is that since the units digit in the sum is odd, Ron must have erased the units digit of the original number. Can you see why?

- The second clue is that once you guess the units digit of the original number, everything falls in place. Can you see why?

Claude

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