Respuesta :
The value of r of the geometric series is 4/5.
What is geometric series?
The geometric series defined as a series represents the sum of the terms in a finite or infinite geometric sequence. The successive terms in this series share a common ratio.
The nth term of a geometric progression is expressed as
Tₙ = arⁿ⁻¹
Where a is the first term, r is the common ratio
Given the formula for the geometric series expressed as
[tex]_3\\\sum{1.3(0.8)^n^-^1}\\n=1[/tex]
Comparing both equations
rⁿ⁻¹ = (0.8)ⁿ⁻¹
r = 0.8
r = 8/10
r = 4/5
Hence, the common ratio is 4/5.
Learn more about geometric series here:
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