Question

what is the fifth term of a sequence whose first term is 5 and whose common ratio is 3

Answer 1

It's a geometric sequence.

The formula of a general term of a geometric sequence:

$a_n=a_1r^{n-1}$

Substitute

$a_1=5,\ r=3,\ n=5$

$a_5=5(3^{5-1})=5(3^4)=5(81)=405$

Answer: The fifth term is equal 405.