document.write( "Question 83996: Is this correct?\r
\n" ); document.write( "\n" ); document.write( "Use the geometric sequence of numbers 1, 1/2, 1/4, 1/8,…to find the following:
\n" ); document.write( "What is r, the ratio between 2 consecutive terms? \r
\n" ); document.write( "\n" ); document.write( "Answer: r = (1/2)/1 = 1/2
\n" ); document.write( "Show work in this space. \r
\n" ); document.write( "\n" ); document.write( "Using the formula for the sum of the first n terms of a geometric series, what is the sum of the first 10 terms? Please round your answer to 4 decimals.
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space.\r
\n" ); document.write( "\n" ); document.write( "S(n) = a(1)[r ^(n + 1) – 1)/(r – 1)
\n" ); document.write( "S(10) = 1[(1/2) ^ 9 – 1] / [(1/2)-1]
\n" ); document.write( "S(10) = [-0.998046875…] / [-0.5] = 1.99609375…\r
\n" ); document.write( "\n" ); document.write( "Using the formula for the sum of the first n terms of a geometric series, what is the sum of the first 12 terms? Please round your answer to 4 decimals.
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space.
\n" ); document.write( "S(n) = a(1)[r ^(n + 1) – 1)/(r – 1)
\n" ); document.write( "S(12) = 1[(1/2) ^ 9 – 1] / [(1/2)-1]
\n" ); document.write( "S(12) = [-0.998046875…] / [-0.5] = 1.99609375…
\n" ); document.write( "n = 12
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #60446 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "The ratio r is the factor to get from term to term. So
\n" ); document.write( "r=nth term/(n-1) term
\n" ); document.write( "\"r=%281%2F8%29%2F%281%2F4%29=%284%2F8%29=1%2F2\"
\n" ); document.write( "\"r=1%2F2\"
\n" ); document.write( "The sequence is cut in half each term, so the sequence is \"%281%2F2%29%5En\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The sum of a geometric series is
\n" ); document.write( "\"S=a%281-r%5En%29%2F%281-r%29\"where a=1
\n" ); document.write( "\"S=%281-%281%2F2%29%5E10%29%2F%281-%281%2F2%29%29\"So plug in n=10 to find the sum of the first 10 partial sums
\n" ); document.write( "\"S=%281-1%2F1024%29%2F%281%2F2%29\"
\n" ); document.write( "\"S=2046%2F1024\"
\n" ); document.write( "So the sum of the first ten terms is \"2046%2F1024\" or 1.99805 approximately\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Use the same formula to find the sum of the 1st 12 terms
\n" ); document.write( "\"S=a%281-r%5En%29%2F%281-r%29\"where a=1
\n" ); document.write( "\"S=%281-%281%2F2%29%5E12%29%2F%281-%281%2F2%29%29\"So plug in n=12 to find the sum of the first 12 partial sums
\n" ); document.write( "\"S=%281-1%2F4096%29%2F%281%2F2%29\"
\n" ); document.write( "\"S=8190%2F4096\"
\n" ); document.write( "So the sum of the first twelve terms is \"8190%2F4096\" or 1.99951 approximately\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );