Question

Determine 7th term in the geometric sequence whise first term is 5 and whose ratio is 2 .

Answer 1

`\bf n^(th)\textit{ term of a geometric sequence}\\\\ a_n=a_1\cdot r^(n-1)\qquad \begin{cases} n=n^(th)\ term\\ a_1=\textit{first term's value}\\ r=\textit{common ratio}\\ ----------\\ n=7\\ a_1=5\\ r=2 \end{cases}\implies a_7=5\cdot 2^(7-1)`

Answer 2

5, 10, 20, 40, 80, 160 and the Seventh term would be 320