Question

What is the 4th term in a geometric sequence for which a1=15 and r=1/3

Answer 1

Geometric goes liket his
$a_n=a_1(r)^{n-1}$
given
a1=15
r=1/3
find a4 or 4th term

$a_4=15( \frac{1}{3} )^{4-1}$
$a_4=15( \frac{1}{3} )^{3}$
$a_4=15 (\frac{1}{27})$
$a_4=\frac{15}{27}$
$a_4=\frac{5}{9}$
4th term is 5/9