Answer
$\dfrac{1}{64}$
Work Step by Step
We know that the $n^{th}$ term of a geometric sequence is given by the formula
$a_n=a_1r^{n-1}$
where $r$=common ratio (we can get this by dividing any two consecutive terms) and $a_1$= the first term
Here, we have
$a_1=1$ and $r=\frac{a_2}{a_1}=\dfrac{\frac{1}{2}}{1}=\dfrac{1}{2}$
Hence,
$a_n=1\left(\dfrac{1}{2}\right)^{n-1}$
Therefore,
$a_{7}=1\left(\dfrac{1}{2}\right)^{7-1}\\a_7=\dfrac{1}{64}$
