document.write( "Question 830824: 7, 21, 8, 72, 9, ? \n" ); document.write( "
Algebra.Com's Answer #500917 by JulietG(1812)\"\" \"About 
You can put this solution on YOUR website!
There might be another possible solution, but the one I see is:
\n" ); document.write( "* 3^x
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\n" ); document.write( "7 * 3^1 = 21
\n" ); document.write( "8 * 3^2 = 72
\n" ); document.write( "9 * 3^3 = 243
\n" ); document.write( "and so on...
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