



 
Hi there. First, think about the 4 in 47. Because it is in the tens place, is there any way it can affect what happens in the units place? The answer is no, so you can be confident that the units digit of 47^{43} is the same as the units digit of 7^{43}. Now look for a pattern. Anything that shows up in the tens column is no longer relevant: Cheers,  


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