document.write( "Question 1064768: What is the units digit of 3^1001 × 7^1002 × 13^1003 ? \n" ); document.write( "

Algebra.Com's Answer #679849 by ikleyn(52812) $\"\"$ $\"About$

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\n" ); document.write( " What is the units digit of 3^1001 × 7^1002 × 13^1003 ?
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document.write( "3^1001 × 7^1002 × 13^1003 = (3*7*13)^1001 * 7*(13^2) = 273^1001 * 1183\r\n" );
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document.write( "Regarding 273^n, the last digit is periodical with the period of 4, so 273^1001 has the last digit 3.\r\n" );
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document.write( "Therefore, the given number has the same last digit as 3*1183, i.e. 9.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The answer is 9.\r
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