What is the sum of an 8-term geometric series if the first term is -11, the last term is 859,375, and the common ratio is -5?

formula of the sum of the 1st nth term in a Geometric Progression:

Sum = a₁(1-rⁿ)/(1-r), where a₁ = 1st term, r = common ratio and n= rank nth of term (r≠1)

Sum = (-11)[1-(-5⁸)] /[(1-(-5)]

Sum = (-11)(1- 390625)/(6)

SUM = 716,144

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priyankapandeyVT priyankapandeyVT · Answer 2 · 2022-08-22T15:13:54+02:00

the sum of an 8-term geometric series if the first term is -11, the last term is 859,375, and the common ratio is -5 is 716144

Given that,
What is the sum of an 8-term geometric series if the first term is -11, the last term is 859,375, and the common ratio is -5 is to be determined.

What is arithmetic progression?

Arithmetic progression is the series of numbers that have common differences between adjacent

What is geometric progression?

Geometric progression is a sequence of series whose ratio with adjacent values remains the same.

the formula of the sum of the 1st nth term in a Geometric Progression:

[tex]Sum = a_1(1-r^n)/(1-r) \\Sum = -11(1 - (-5)^8)/(1+5)\\sum = -11(1 - 390625)(6)\\Sum = 716144[/tex]

Thus, the required sum of the 8-term geometric series is 716,144.

Learn more about geometric progression here: https://brainly.com/question/4853032

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