a = 31 1/4 = 125/4
ar^(n-1) = 2
r^(n-1) = 8/125
Now, 8/125 = (2/5)^3
Looks to me like
r = 2/5 and n=4
and the sequence is thus
125/4, 25/2, 5, 2
I think you'll find it adds up to 203/4
The first term of a geometric sequence is 31(1/4),the last term is 2 and the sum of the associated series is 50(3/4).what is the common ratio and how many terms are there in the series?
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