1. You take a $5,000 loan with an interest rate of 10% and pay off a constant principal portion of $200 every year. Use the arithmetic progression.
- Find the interest payment during the 17th year. (a17 = ?)
- What is the total amount of interests for 20 years? (S20 = ?)
2. Starting with $2,000 on March 3, you deposit $500 23 days from March 3, withdraw $800 69 days from March 3, and deposit $600 121 days from March 3. If your final balance is $2,458 150 days from March 3, what is the simple interest rate for your account? Use the Banker's rule.