SOLUTION: determine the number of terms in finite arthmetic sequence. -6,-3,0,...,222

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Question 762542: determine the number of terms in finite arthmetic sequence.
-6,-3,0,...,222
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
What is the general term? First term is -6 and common difference is +3.
Any term a is a=%28-6%29%2B%283%29%2A%28n-1%29
a=-6%2B3%28n-1%29.

If a=222, then you find the value of n by equating the formula with the value of a.

highlight%28-6%2B3%28n-1%29=222%29
Solve for n.