document.write( "Question 44629: I've got this problem (see below). I've worked through problems 1b - 1d, but I am stuck with how to answer 1e. Can someone help?\r
\n" ); document.write( "\n" ); document.write( "Thanks A Bunch!\r
\n" ); document.write( "\n" ); document.write( "1) Use the arithmetic sequence of numbers 1, 3, 5, 7, 9,…to find the following:
\n" ); document.write( "a) What is d, the difference between any 2 terms? \r
\n" ); document.write( "\n" ); document.write( "Answer: d = 2\r
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\n" ); document.write( "\n" ); document.write( "The difference between any two terms = (n+1 ) th term - (n) th term \r
\n" ); document.write( "\n" ); document.write( "So, the difference d = 3-1 = 5-3 = 7-5 = 2 \r
\n" ); document.write( "\n" ); document.write( "Answer d = 2 \r
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\n" ); document.write( "\n" ); document.write( "b) Using the formula for the nth term of an arithmetic sequence, what is 101st term?
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\n" ); document.write( "Answer: nth term = 201\r
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\n" ); document.write( "\n" ); document.write( "Show work in this space. \r
\n" ); document.write( "\n" ); document.write( "Given a = first term = 1
\n" ); document.write( "n = 101
\n" ); document.write( "d = 2
\n" ); document.write( "putting above values in formula 1
\n" ); document.write( "nth term = 1 + (101-1) * 2
\n" ); document.write( "= 1 + 200 = 201
\n" ); document.write( "So, nth term = 201 \r
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\n" ); document.write( "\n" ); document.write( "c) Using the formula for the sum of an arithmetic series, what is the sum of the first 20 terms? \r
\n" ); document.write( "\n" ); document.write( "Answer: 400 \r
\n" ); document.write( "\n" ); document.write( "Show work in this space
\n" ); document.write( "n = 20
\n" ); document.write( "a = first term = 1
\n" ); document.write( "So, sum = 20 / 2 (2 * 1 + 19 * 2)
\n" ); document.write( "= 10 * (40)
\n" ); document.write( "sum = 400 \r
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\n" ); document.write( "\n" ); document.write( "d) Using the formula for the sum of an arithmetic series, what is the sum of the first 30 terms? =n/2(a +(n-1)d)…………..(1)\r
\n" ); document.write( "\n" ); document.write( "Answer: 900\r
\n" ); document.write( "\n" ); document.write( "Show work in this space
\n" ); document.write( "given that n = 30
\n" ); document.write( "a = first term =1
\n" ); document.write( "= 30 / 2 (2 * 1 + 29 * 2)
\n" ); document.write( "=15 * (60)
\n" ); document.write( "= 900 \r
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\n" ); document.write( "\n" ); document.write( "e) What observation can you make about these sums of this series (HINT: It would be beneficial to find a few more sums like the sum of the first 2, then the first 3, etc.)? Express your observations as a general formula in \"n.\"\r
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Algebra.Com's Answer #29503 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
When \"d\" is a positive number the sum of terms gets
\n" ); document.write( "increasingly greater as you add more terms.\r
\n" ); document.write( "\n" ); document.write( "The sum of \"n\" terms is n times the average of the
\n" ); document.write( "1st and the nth term, i.e. S(n)=(n)[a+(n-1)d]/2\r
\n" ); document.write( "\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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