document.write( "Question 251149: A, B, and C each can be any digit 0 through 9, possibly the same. The seven-digit whole number: 20ABC01 is a perfect square. What is the middle digit, B?\r
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Algebra.Com's Answer #184105 by Edwin McCravy(20086) $\"\"$ $\"About$

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A, B, and C each can be any digit 0 through 9, possibly the same. The seven-digit whole number: 20ABC01 is a perfect square. What is the middle digit, B?\r
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document.write( "The smallest possible number 20ABC01 could be, (even\r\n" );
document.write( "if it weren't necessarily a perfect square) is 2000001\r\n" );
document.write( "and the largest it could be would be 2099901.  The\r\n" );
document.write( "square roots of those are 1414.213916 and 1449.103516\r\n" );
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document.write( "Therefore the first two digits of the square root of 20ABC01\r\n" );
document.write( "must be 14, and it is between 1414 and 1449\r\n" );
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document.write( "Looking at a list of squares of the first 100 integers,\r\n" );
document.write( "we see that the only perfect squares that end in 01 are \r\n" );
document.write( "squares of numbers that end in 01, 49, 51, and 99\r\n" );
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document.write( "The only square root 20ABC01 could have and be in that\r\n" );
document.write( "range would be 1449, and  is 2099601.\r\n" );
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document.write( "So the middle digit is 9, choice E\r\n" );
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document.write( "Edwin

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