1.

Check wheather 7^n can end with the digit zero for any natural number​

Answer»

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Unit digit  |  7ⁿ

      7        |   7¹

      9        |  7²

      3        |  7³

      1         |  7⁴

If we MULTIPLY SEVEN again to 7⁴, it will repeat again. Therefore, it is possible to get 1, 3, 7, 9.

It is not possible to get 0.



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