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Series: Arithmetic Progressions
The sum of the arithmetic series of 8 terms:
16 + 15.50 + 15 + ... 12.50 = to 3 dps

tickcross



Worked Solution

One formula for the sum of an Arithmetic Series is
number of terms × average term = n ×
first + last
---
2
Here the first term is 16, the last term is 12.5 and there are 8 terms
The sum of this series is therefore 8 ×
16 + 12.5
---
2
 = 114 to 3 dps

© MEI Produced by Dr Ron Knott, revised 25 September 2005
tom . button [AT] mei . org . uk 		Test reference: SeriesAPsum.html?ref=43005