Asked by John

Can you please explain step by step on how to do each of these two problems below? And then tell me whether it involves an arithmetic sequence or a geometric sequence I also need the work shown out for both problems thank you.

1). A person hired a firm to build a CB radio tower. The firm charges $100 for labor for the first 10 feet. After that, the cost of the labor for each succeeding 10 feet is $25 more than the preceding 10 feet. That is, the next 10 feet will cost $125, the next 10 feet will cost $150, etc. How much will it cost to build a 90-foot tower?

2). A person deposited $500 in a savings account that pays 5% annual interest that is compounded yearly. At the end of 10 years, how much money will be in the savings account?
Answered by Reiny
ost = 100 + 125 + 150 + 175 + for 9 terms

This is an arithmetic series
a = 100
d = 25
n = 9
Sum(9) = (9/2)(2(100) + (9-1)(25))
= (9/2)(200 + 200) = 1800

2)

amount = 500(1.05)^10 = 814.45
Answered by michelle
what is the arithmetic oe 3,5,7,9,and 11
Answered by cathyj
Mary has been working at the university for 25 years, with an excellent record of service. As a result, the board wants to reward her with a bonus to her retirement package. They are offering her $75,000 a year for 20 years, starting one year from her retirement date and each year for 19 years after that date. Mary would prefer a one-time payment the day after she retires. What would this amount be if the appropriate interest rate is 7%?