document.write( "Question 267390: unit digit of a sum
\n" ); document.write( "11^11 + 14^14 + 16^16 whats the unit digit of this sum \n" ); document.write( "

Algebra.Com's Answer #196250 by drk(1908) $\"\"$ $\"About$

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\n" ); document.write( "11^1 = 11
\n" ); document.write( "11^2 = 121
\n" ); document.write( "11^3 = 1331
\n" ); document.write( "I see the pattern of ending in 1.
\n" ); document.write( "---
\n" ); document.write( "14^1 = 14
\n" ); document.write( "14^2 = 196
\n" ); document.write( "14^3 = 2744
\n" ); document.write( "when the power is odd it ends in 4, and when it is even it ends in 6.
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\n" ); document.write( "16^1 = 16
\n" ); document.write( "16^2 = 256
\n" ); document.write( "16^3 = 4096
\n" ); document.write( "The units digit is always 8.
\n" ); document.write( "---
\n" ); document.write( "we get 1 + 6 + 6 = 13
\n" ); document.write( "The final units digit will be 3. \n" ); document.write( "

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