What is the highest number that can be got from 4383 by moving exactly 2 matches?

Question

What is the highest number that can be got from 4383 by moving exactly 2 matches?

Number 1 has got 2 matches, so I thought it will be 47831 as I remove two matches from second number (3), but it isn't the highest possible.

Format is same like this (1 is only number with only two matches)

Does anybody know solution?

Answer 1

If you want to play with notation, you could have 4^783 or $438^3$ depending on what you allow.

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Of course with actual matches, the caret would be squished in between the 4 and the 3. Might be considered cheating because really you should move the whole 4, as I did in the drawing. On the other hand:

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Only moves 2 matches and would be how you would write $438^3 = 84,027,672$

Answer 2

I am guessing 71393. Rotate the horizontal match of the leading 4 to split it into two ones, and grab one out of the 8 to turn the leading 1 into a 7.

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Answer 3

7^983 is the highest number. The 4 changes to a 7, and the 3 changes to a 9.

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