document.write( "Question 363479: A number is called \"even-odd\" if it is halfway between an even integer and an odd integer . if x is an even-odd number, which of the following must be true ?\r
\n" ); document.write( "\n" ); document.write( "I 2x is an integer\r
\n" ); document.write( "\n" ); document.write( "II 2x is even-odd\r
\n" ); document.write( "\n" ); document.write( "III x is halfway between two even integers\r
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\n" ); document.write( "\n" ); document.write( "(A) I only\r
\n" ); document.write( "\n" ); document.write( "(B) II only\r
\n" ); document.write( "\n" ); document.write( "(c) I and II only \r
\n" ); document.write( "\n" ); document.write( "(D) II and III only \r
\n" ); document.write( "\n" ); document.write( "(E) I, II, and III\r
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Algebra.Com's Answer #259171 by J2R2R(94)\"\" \"About 
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Let us say the two numbers are 2m + 1 (odd) and 2n (even) where m and n are integers irrespective of being odd or even.\r
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\n" ); document.write( "\n" ); document.write( "Halfway between them is (2m + 1 + 2n)/2 = (m + n) + ½\r
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\n" ); document.write( "\n" ); document.write( "So the even-odd number X must be of the form N + ½ where N can be any integer.\r
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\n" ); document.write( "\n" ); document.write( "Therefore\r
\n" ); document.write( "\n" ); document.write( "2X is an integer (odd)\r
\n" ); document.write( "\n" ); document.write( "2X cannot be an even-odd number since 2X is an integer and not of the form N + ½\r
\n" ); document.write( "\n" ); document.write( "X cannot be halfway between two even integers since half way between two even integers is an integer too and X is of the form N + ½\r
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\n" ); document.write( "\n" ); document.write( "Therefore only the first one is correct which means the answer is A.
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