SOLUTION: First term is 1 Common difference is 4. Sum of the terms is 153. How many terms are in the series. Show method of calculation.

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Question 935982: First term is 1 Common difference is 4. Sum of the terms is 153. How many terms are in the series. Show method of calculation.
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
A%5Bn%5D=1%2B4%28n-1%29, general term for the sequence.

%28A%5B1%5D%2BL%29%28n%2F2%29, L is for LAST term in the sequence,
The formula for sum of a sequence of n terms.
Better, the expression is %28A%5B1%5D%2BA%5B1%5D%2B4%28n-1%29%29%28n%2F2%29.

Your sum 153, you want to find n.
%281%2B%281%2B4%28n-1%29%29%29%28n%2F2%29=153

The first goal is to understand all that, leading to the equation just given. The rest is to just simplify that equation and solve for n.