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41 votes
Fond the 7th term of the geometric sequence whose common ratio is 1/3 and whose first term is 4

User Moona
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1 Answer

9 votes
9 votes

Answer:


a_7=(4)/(729)

Explanation:

General form of geometric progression:
a_n=ar^(n-1)

(where
a is the initial term and
r is the common ratio)

Given:


  • a=4

  • r=\frac13


\implies a_n=4\left(\frac13\right)^(n-1)

Therefore, when n = 7:


\implies a_7=4\left(\frac13\right)^(7-1)


\implies a_7=4\left(\frac13\right)^(6)


\implies a_7=4\left((1^6)/(3^6)\right)


\implies a_7=4\left((1)/(729)\right)


\implies a_7=(4)/(729)

User Shammery
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