SOLUTION: In the arithmetic sequence where the third term is 9, how many terms are added together to get a sum of 153.

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Question 849932: In the arithmetic sequence where the third term is 9, how many terms are added together to get a sum of 153.
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
153 = ½(2a + d(n-1))n
9= a + 2d
Some possible answers
a = 1, d = 4, n = 9
a = 99, d = -45, n = 2
a = 93, d = -42, n = 3
a = -57, d = 33, n = 6