document.write( "Question 937701: Which of these sequences is a geometric sequence?\r
\n" ); document.write( "\n" ); document.write( "1, 2, 4, 7, 11, 16, 22, …\r
\n" ); document.write( "\n" ); document.write( "2, 4, 8, 14, 22, 38, …\r
\n" ); document.write( "\n" ); document.write( "3, 6, 9, 12, 15, 18, 21, …\r
\n" ); document.write( "\n" ); document.write( "3, 9, 27, 81, 343, 729, …
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Algebra.Com's Answer #571144 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "If the sequence is geometric, then there is a common ratio, we must think in terms of multiplication previous term by common ratio \"r\" to get next term in sequence.\r
\n" ); document.write( "\n" ); document.write( "The r-value can be calculated by dividing \"any\"\"+two\"\"+consecutive\" terms in a geometric sequence. \r
\n" ); document.write( "\n" ); document.write( "The formula for calculating the Common Ratio \"r\" is:\r
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\n" ); document.write( "\n" ); document.write( "\"r+=+%28nth_+term%29%2F%28%28n-1%29th+_term%29\"\r
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\n" ); document.write( "\n" ); document.write( "1.
\n" ); document.write( "\"2\", \"4\", \"7\", \"11\", \"16\", \"22\", \"29\", \"37\", … \r
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\n" ); document.write( "\n" ); document.write( "\"r+=+4%2F2=2\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+7%2F4=1.75\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+11%2F7=1.571428571428571\"\r
\n" ); document.write( "\n" ); document.write( " there is no common ratio \"r\", \"not\" a geometric sequence\r
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\n" ); document.write( "\n" ); document.write( "2.
\n" ); document.write( "\"4\", \"8\", \"14\", \"22\", \"38\", … \r
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\n" ); document.write( "\n" ); document.write( "\"r+=+8%2F4=2\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+14%2F8=1.75\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+22%2F14=1.571428571428571\"\r
\n" ); document.write( "\n" ); document.write( "there is no common ratio \"r\", \"not\" a geometric sequence\r
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\n" ); document.write( "\n" ); document.write( "3.
\n" ); document.write( "\"6\", \"9\", \"12\", \"15\", \"18\", \"21\", … \r
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\n" ); document.write( "\n" ); document.write( "\"r+=+9%2F6=3%2F2\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+12%2F9=4%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+15%2F12=5%2F4\"\r
\n" ); document.write( "\n" ); document.write( "there is no common ratio \"r\", \"not\" a geometric sequence\r
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\n" ); document.write( "\n" ); document.write( "4.\r
\n" ); document.write( "\n" ); document.write( "9, 27, 81, 343, 729, …\r
\n" ); document.write( "\n" ); document.write( "\"r+=+27%2F9=3\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+81%2F27=3\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+343%2F81=4.24\" \r
\n" ); document.write( "\n" ); document.write( "\"r+=+729%2F343=2.12536443148688\" there is no common ratio \"r\", \"not\" a geometric sequence\r
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\n" ); document.write( "\n" ); document.write( "since you have to have one solution, I think the term \"+343\" is wrong because first three terms have common ratio \"3\",if we multiply \"81%2A3\" we got \"243\" and \"r+=243%2F81=3\" \r
\n" ); document.write( "\n" ); document.write( "and next one will be \"r+=+729%2F243=3\"\r
\n" ); document.write( "\n" ); document.write( "there is common ratio \"r=3\", means the sequence \"9\", \"27\", \"81\", \"243\", \"729\", … \"IS\" a geometric sequence\r
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