If n = 7^11 – 7, what is the units digit of n? Choose the most appropriate option.
A) 0
B) 1
C) 4
D) 6
E) 8
Always divide the power (incase 11) by 4 and use the remainder as the new power. The question now becomes 7^3 - 7. Now 7^3 has last digit 3. Since 7^11 (or for that matter 7^3) is greater than 7, we subtract 7 from 13 ( the 10+3 --&gt; 10 has come from carry over from the tenth place). thus 13 - 7= 
<gadget id="calculator">13 - 7</gadget>
<output>6</output>
6 is the answer. Option 6
<result>D</result>
If n = 7^11 – 7, what is the units digit of n?