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Find the common ratio and find the 15th term.
1,3,9,27...
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User Mashal
by
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1 Answer

5 votes

Answer:

4782969

Explanation:

the equation for finding a term (IN A GEOMETRIC series) is a1(r)^(n-1)

a1=first term

r=ratio

n=the number you want

you can see that the sequence increases by the eponent of 3 increasing y 1 each time. So for the first time 3^0=1,3^1=3, 3^2=9 and so on. So we can determine that the ratio is 3.

so now we can plug all that information into the equation

1(3)^(15-1)=the 15th term

4782969=15th term

Hope that helps :)

User Coagmano
by
6.0k points