SOLUTION: The sum of the arithmetic is 192 with a last term of 27 and a common difference of 2. Find the number of terms.

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Question 826126: The sum of the arithmetic is 192 with a last term of 27 and a common difference of 2. Find the number of terms.
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
Setting up our equations we find:
192=%28n%2F2%29%28a%5B1%5D%2B27%29 and 27=a%5B1%5D%2B%28n-1%29%2A2

Solving the system by substitution leads to two possible solutions, both valid.
a%5B1%5D=5, n=12

or
a%5B1%5D=-3, n=16