### Home > A2C > Chapter 12 > Lesson 12.3.1 > Problem 12-129

12-129.

Joe's dad is only 40, but He's already thinking about retiring. If he retires early at age 55, he will receive an annual pension starting at $30,000 and increasing at a rate of 3% each year to account for inflation. If he waits until he is 65, his pension will be a larger percentage of his salary at that time. He figures that it will be about $60,000 to start and the same 3% increase after that for inflation. He wants to know which plan will pay out the largest total by age 80. Show him how to find out the answer to his question. Homework Help ✎

Find the sum of the geometric series defined by *t*(*n*) = 30000(1.03)^{n}^{ − 1} from 1 to 25

and the sum of the geometric series defined by *t*(*n*) = 60000(1.03)^{n}^{ − 1} from 1 to 15.