Question

what is the value of the fourth term in a geometric sequence for which a 1 10 and r 0.5

Answer 1

First off, what is the equation for the geometric sequence?

Answer 2

\(\large\color{black}{ a_1 =10}\) , \(\large\color{black}{ r =0.5}\)

there is a form for any nth term: \(\large\color{black}{ a_{n}=a_1\times r^{n-1}}\)

Answer 3

in your case, it is : \(\large\color{black}{ a_{4}=a_1\times r^{4-1}}\)

\(\large\color{black}{ \Downarrow}\)

\(\large\color{black}{ a_{4}=a_1\times r^{3}}\)

Answer 4

you know the \(\large\color{black}{a_1}\) and the \(\large\color{black}{ r}\).
If you have questions, ask.