Answer
The common ratio is 3. The 5th term is 162. $a_n = 2(3)^{(n-1)}$
Work Step by Step
We are given the terms 2,6,18,54. Since each term is multiplied by 3 to get to the next term the common ratio is 3. The 5th term is therefore the 4th term (54) $\times$ 3 = 162. To write a formula for the nth term of the geometric sequence start with the form $a_n = a(r)^{(n-1)}$ since a (the first term) = 2 and r (the common ratio) = 3 the formula is $a_n = 2(3)^{(n-1)}$
