# Calculate the interest rate

Hello, I have difficulty understanding part of the code of the following question:

You want to invest capital 0 for n years at an annual interest rate of i%.
The relation is given by: = 0*(1 + )^.
Write a program giving you the amount earned, the interest ( = − 0) of your
investment, as well as the equivalent monthly interest rate under the database
provided. = (1 + )^(1/12) − 1.

The following would be the answer:

from math import *

C0 = float(input(‘Starting capital: ‘))
i = float(input("Annual interest rate: "))
i = i / 100
u = 1 + i
n = int(input("Number of years: "))
print(’’)

C = C0 * (un)
I = C - C0
im = u
(1/12) - 1

C = int(100 * C)/100
I = int(100 * I)/100
im = int(10000 * im)/100

print(‘Capital after’, n, ‘years:’, C, ‘€’)
print('Interest: ', I, ‘€’)
print("Monthly interest rate: ", im, ‘%’)

The code I don’t understand is the following:

I do not understand why this was written, what it means and how it affects the code:

C = int(100 * C)/100
I = int(100 * I)/100
im = int(10000 * im)/100

Many thanks for who can help me out!