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The sum of the first nine terms in a sequence is 49,205. Each term is 3 times the previous term. What is the third term?

User Mychael
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1 Answer

1 vote

Answer:

a₃ = 32 805

Explanation:

Each term is 3 times the previous term:

r = 3

The sum of the first nine terms in a sequence is 49,205:


S_n=a_1\cdot(1-q^n)/(1-q)\\\\\\49205=a_1\cdot(1-3^9)/(1-3)\\\\49205=a_1\cdot(1-19683)/(-2)\\\\49205=a_1\cdot9841\\\\a_1=5

What is the third term?


a_n=a_1\cdot q^(n-1)\\\\a_3=5\cdot3^8=32805

User Tonyrobbins
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