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Geometric Sequence find the 23rd term.

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RTCNTC

Banned
Jan 31, 2017
1,358
A geometric sequence has an initial value of 25 and a common ratio of 1.8. Write a function to represent this sequence . Find the 23rd term.

My Effort:

The needed function is

a_n = a_1•r^(n-1), n is the 23rd term, r is the common ratio and a_1 is the initial value.

a_23 = 25•(1.8)^(23 - 1)

Is this correct?
 

skeeter

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MHB Math Helper
Mar 1, 2012
639
yes
 
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RTCNTC

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Jan 31, 2017
1,358
a_23 = 25 * 1.8(23-1)

a_23 = 25 * (1.8)^(22)

a_23 = 10326071.3

Correct?
 

Country Boy

Well-known member
MHB Math Helper
Jan 30, 2018
368
To one decimal place, yes. Do you have a reason for choosing to write the answer to one decimal place?