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The common ratio of a geometric series is 3 and the sum of the first 8 terms is 3280.

What is the first term of the series?

User Joshpt
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Answer:

The first term of the geometric series is 1

Explanation:

In this question, we are tasked with calculating the first term of a geometric series, given the common ratio, and the sum of the first 8 terms.

Mathematically, the sum of terms in a geometric series can be calculated as;

S = a(r^n-1)/( r-1)

where a is the first term that we are looking for

r is the common ratio which is 3 according to the question

n is the number of terms which is 8

S is the sum of the number of terms which is 3280 according to the question

Plugging these values, we have

3280 = a(3^8 -1)/(3-1)

3280 = a( 6561-1)/2

3280 = a(6560)/2

3280 = 3280a

a = 3280/3280

a = 1

User Preeve
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