5, 10, 20, 40, . . .
SolutionStep1 Find the common ratio(r)[tex]r=\frac{a_2}{a_1}=\frac{10}{5}=2[/tex]Step 2The geometric sequence formula
[tex]a_n=a_1\times r^{n-1}[/tex]Step 3[tex]\begin{gathered} r=2,\text{ } \\ a_1=5 \\ n=12 \end{gathered}[/tex]Step 4[tex]\begin{gathered} a_{12}=5\times2^{12-1} \\ a_{12}=5\times2^{11} \\ a_{12}=10240 \end{gathered}[/tex]The final answer The 12th term of the geometric sequence is 10240