Unit's Digit. Pretty Easy Right?

Number Theory Level 3

True or false :

$\quad$ The unit's digit for $5^{n}$ is always $5$ for any whole number $n$ .

Can't be determined No, This is not true for every whole number

n

Yes, This is true for every whole number

n

1 solution

Anirudha Brahma
Apr 18, 2016

$\text{This statement is true for every whole number except 0}$

$\text{In the case of n = 0 The unit's digit is 1.}$

Simple standard approach. Watch out for the edge cases!