Use the formula for the general term (the nth term) of a geometric sequence to find the indicated term of the sequence
with the given first term, a1, and common ratio, r.
-Find a7 for the sequence 0.7, 0.07, 0.007, . . .
A) 0.00000007
B) 0.0000007
C) 0.00000001
D) 0.000007

Question

Quizplus · Accepted Answer

The formula for the nth term of a geometric sequence is $a_n = a_1 \cdot r^{(n-1)}$. Here, $a_1 = 0.7$ and $r = 0.1$ (since each term is 1/10th of the previous one). Plugging in the values for $a_7$, we get $a_7 = 0.7 \cdot (0.1)^{6} = 0.7 \cdot 0.000001 = 0.0000007$.

Use the Formula for the General Term (The Nth Term)