document.write( "Question 270153: 3, 5,–5...
\n" ); document.write( "The first term in the sequence of numbers shown above is 3. Each even–numbered term is 2 more than the previous term and each odd–numbered term, after the first, is –1 times the previous term. For example, the second term is 3 + 2, and the third term is (–1) × 5. What is the 55th term of the sequence? \r
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Algebra.Com's Answer #197949 by Edwin McCravy(20056)\"\" \"About 
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3, 5,–5...
\n" ); document.write( "The first term in the sequence of numbers shown above is 3. Each even–numbered term is 2 more than the previous term and each odd–numbered term, after the first, is –1 times the previous term. For example, the second term is 3 + 2, and the third term is (–1) × 5. What is the 55th term of the sequence? \r
\n" ); document.write( "\n" ); document.write( "(A)–5 (B) –3 (C) –1 (D) 3 (E) 5
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document.write( "1 is odd, and 1 more than a multiple of 4, since 1=4*0+1, and the 1st term is 3\r\n" );
document.write( "2 is even, but an even NON-multiple of 4, and the 2nd term is 3+2 or 5\r\n" );
document.write( "3 is odd, and 1 more than an even NON-multiple of 4 and the 3rd term is -5\r\n" );
document.write( "4 is even, a multiple of 4, since 4=4*1, and the 4th term is -5+2 or -3\r\n" );
document.write( "5 is odd, and 1 more than a multiple of 4, and the 5th term is 3\r\n" );
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document.write( "And we're back to where we started, so the rule for the sequence is\r\n" );
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document.write( "I. If n is odd, and 1 more than a multiple of 4, then the nth term is 3\r\n" );
document.write( "II. If n is odd, and 1 more than an even NON-multiple of 4, then the nth term is -5\r\n" );
document.write( "III. If n is even, but a NON-multiple of 4, the nth term is 5\r\n" );
document.write( "IV. If n is even, and a multiple of 4, the nth term is -3 \r\n" );
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document.write( "We want the 55th term.  55 is odd, and is 1 more than 54, an even but \r\n" );
document.write( "NON-multiple of 4, so the 55th term is in category II above, and is \r\n" );
document.write( "therefore -5 \r\n" );
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document.write( "The correct choice is (A) -5\r\n" );
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document.write( "Edwin
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