Question

What is the fifth term of the geometric sequence a1=10, a2=5, a3=2.5, a6=.31251.25.625.5-.625

Answer 1

Determine the common ratio for the sequence.

$\begin{gathered} r=\frac{a_2}{a_1} \\ =\frac{5}{10} \\ =\frac{1}{2} \end{gathered}$

Determine the fifthn term of the sequence.

$\begin{gathered} a_5=a_1(r)^{5-1} \\ =10\cdot(\frac{1}{2})^4 \\ =10\cdot0.0625 \\ =0.625 \end{gathered}$

So fifth term of sequence is 0.625.