Question

Write a program in Python that computes the interest accrued on an account.

• You can modify the “futval.py” program given in Chapter 2 to accomplish it. Your program should use a counted loop rather than a formula.
• It should prompt the user to enter the principal amount, the yearly interest rate as a decimal number, the number of compounding periods in a year, and the duration.
• It should display the principal value at the end of the duration.
  • To compute the value in 10 years for example, the program should loop 10 * periods times and accrue rate /period interest on each iteration.
  • If the principal is $1,000.00, yearly interest rate is 0.04 (4%), compounding periods in a year are 4, and the duration is 10 years, then the program should display $1488.86.

futval.py

def main():
   print(" This Program calculates the future value")
   print(" of a 10-year investment. ")
   principal = eval(input("Enter the initial principal: "))
   apr = eval(input("Enter the initial principal: "))
   for i in range(10):
       principal = principal *(1 +apr)
       print("The value in 10 years is:",principal)
       main()

Answer 1

def main():
    print("This program calculates the future value of a n-year investment.")
    n = int(input("Enter the number of years n: "))
    num_periods = int(input("Enter number of compounds periods in an year: "))
    principal = float(input("Enter the initial principal: "))
    apr = float(input("Enter the annual interest rate: ")) / num_periods
    for i in range(n * num_periods):
        principal = principal * (1 + apr)
    print("The value in 10 years is: {:.2f}".format(principal))


main()