SOLUTION: Please help me find the sum of the following series: t1 = -4 tn = 66 n = 15

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Question 1162979: Please help me find the sum of the following series:
t1 = -4
tn = 66
n = 15
Answer by ikleyn(52793)   (Show Source): You can put this solution on YOUR website!
.

Find the average of the first and last terms  A =  =  =  = 31.


Then multiply it by the number of term.  You will get the value of the sum = 31*15 = 465.  ANSWER

Solved.

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    - Problems on arithmetic progressions
    - Word problems on arithmetic progressions
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