SOLUTION: If S8 = 1530 and r = 2, what is a1?
3
6
9
12
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Question 1041318: If S8 = 1530 and r = 2, what is a1?
3
6
9
12
Found 2 solutions by Theo, jim_thompson5910:
Answer by Theo(13342) (Show Source): You can put this solution on YOUR website!
A1 = 6
here's why.
formula for Sn = A1 * (1 - r^n) / (1 - r)
r = 2
n = 8
S8 = 1530
formula becomes 1530 = A1 * (1 - 2^8) / (1 - 2)
simplify to get 1530 = A1 * (-255 / (-1))
simplify further to get 1530 = A1 * 255
divide both sides of the equation by 255 to and solve for A1 to get A1 = 1530 / 255 = 6
A1 = 6
S8 = 6 * (1 - 2^8) / (1 - 2) = 6 * -255 / -1 = 6 * 255 = 1530
solution is confirmed as good.
A1 = 6
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
The final answer is 6
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