Yahoo Answers: Answers and Comments for Sum of the terms pf arithmetic progression? [Mathematics]
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Tue, 28 Jul 2009 07:24:44 +0000
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Yahoo Answers: Answers and Comments for Sum of the terms pf arithmetic progression? [Mathematics]
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From ?: 1) This is an arithmetic sequence, modelled by...
https://answers.yahoo.com/question/index?qid=20090728072444AAeD6Iy
https://answers.yahoo.com/question/index?qid=20090728072444AAeD6Iy
Tue, 28 Jul 2009 08:04:35 +0000
1) This is an arithmetic sequence, modelled by the formula
Sn = n/2 * (2a1 + (n1)d), where
 Sn is the sum of the number of terms, which is 880
 a1 is the initial value, which is 25
 n is the number of terms, which we are trying to find
 d is the difference between consecutive terms, which is 2.
This gives
880= (n/2) * (50 +2(n1))
880= (n/2) * (48 + 2n)
n^2 + 24n  880 = 0
n = 20
Therefore it will take him 20 days to make 5550 peso.
2) Tn = a + d(n1)
Tn = 25000  500 (191)
Tn = 16000
Therefore, the value of the 19th place is 16000 pesos.
These are just formulas for finding terms or sums of arithmetic sequences. Your book should give an explanation of these. If you need more information, look at the following two links:
http://www.ltcconline.net/greenl/courses/103B/seqSeries/ARITSEQ.HTM
http://www.mathguide.com/lessons/SequenceArithmetic.html