SOLUTION: Given 50+42+34+26+18+ ... find n such that Sn=182

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Question 827009: Given 50+42+34+26+18+ ... find n such that Sn=182
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
a%5B1%5D=50 and d=-8



so
%0D%0A182=-4n%5E2%2B54n%0D%0A

which has only one suitable solution, n=7 (why?)

checking...
50+42+34+26+18+10+2=182