The DISPUTOR is similar to a calculator, but it behaves a little oddly. When you type in a number, the DISPUTOR doubles the number, then reverses the digits of this result, then adds 2 and displays the final result. I type in a whole number between 10 and 99 inclusive. Which of the following could be the final result displayed?
Select one option, then click Submit.
39
41
42
43
45
Select an option, then submit.
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Junior Mathematical Challenge 2000 (2000)
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