SOLUTION: Sn=1550, n=3, r=5 Find a1.

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Question 1082519: Sn=1550, n=3, r=5 Find a1.
Answer by ikleyn(52794)   (Show Source): You can put this solution on YOUR website!
.
a + a*5 + a*5^2 = 1550  ---->

a*(1 + 5 + 25) = 1550  ---->

31a = 1550  ---->  a =  = calculate.


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