``3rd term:` a_1 = 16, a_4 = 27/4` Find the indicated term of the geometric sequence.

You need to write the following formula such that:

a_4 = a_3*q

`a_3 = a_2*q`

`a_2 = a_1*q`

Replace `a_1*q` for `a_2` , such that:

`a_3 = a_1*q*q => a_3 = a_1*q^2`

Replace `a_1*q^2` for `a_3` such that:

`a_4 = a_1*q^2*q => a_4 = a_1*q^3 => q^3 = (a_4)/(a_1) => q = root(3)((a_4)/(a_1))`

`q = root(3)((27/4)/(16)) => q = root(3)((3^3)/(4^3))`

`q = 3/4`

You may find `a_3` such that:

`a_3 = (a_4)/q => a_3 = (27/4)/(3/4) => a_3 =9`

Hence, evaluating` a_3` yields `a_3 = 9.`