document.write( "Question 1183971: 1,3,5,7,13,12,25,18,? \n" ); document.write( "

Algebra.Com's Answer #814492 by greenestamps(13200) $\"\"$ $\"About$

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\n" ); document.write( "The message in the response from the other tutor is that any next number will form a valid sequence, so \"?\" can be any number.

\n" ); document.write( "The general answer to ANY question like this is that there is no way to know what the \"correct\" answer is.

\n" ); document.write( "So questions like this must be considered as recreational puzzles -- not as formal math problems.

\n" ); document.write( "Take as much, or as little, time as you want looking for a relatively simple pattern that will generate the given sequence of numbers.

\n" ); document.write( "One strategy that often works is to view the given sequence as two (or more) spliced sequences. Using that strategy on this example gives a big hint as to what the expected answer is.

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document.write( "Given sequence...\r\n" );
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document.write( "   1  3  5  7 13 12 25 18 __\r\n" );
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document.write( "Separated into two separate sequences...\r\n" );
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document.write( "   1     5    13    25    __\r\n" );
document.write( "      3     7    12    18

\n" ); document.write( "Look for similar patterns in those two sequences to determine the logical next number in the first sequence....

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