SOLUTION: find the sum of each series -60 + (-59) + (-58) + . . . . + 87 + 88 + 89 + 90

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Question 205220: find the sum of each series
-60 + (-59) + (-58) + . . . . + 87 + 88 + 89 + 90
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the sum of each series
-60 + (-59) + (-58) + . . . . + 87 + 88 + 89 + 90
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Formula: S(n) = (n/2)(1st + last)
n = 90+1+60 = 151 terms
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S(151) = (151/2)(-60+90)
= 75.5*30
= 2265
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Cheers,
Stan H.