19.83 x 1.07 = <span>21.218
$21.22</span>
You are supposed to make a claim then prove it using evidence you are already given.
Given:
second term = 18
fifth term = 144
The nth term of a geometric sequence is:

Hence, we have:

Divide the expression for the fifth term by the expression for the second term:

Substituting the value of r into any of the expression:

Hence, the explicit rule for the sequence is:
I'm pretty sure 10/63 is simplified.