Please explain logic to solve this problem..

Question

You take a loan from a friend and need to calculate how much you will owe him after 3 months.
You are going to pay him back 10% of the remaining loan amount each month.
Create a program that takes the loan amount as input, calculates and outputs the remaining amount after 3 months.

Answer 1

You take money from a friend
Let's say 100$
The first month you should pay him 10% of the remaining money, so you give him back 100$ * 10%= 10$

The remaining will be 90$, the next month you will pay 10% of the 90$, so you give back 9$.

The remaining will be 81$, the third month you will pay 10% of the 81$, so you'll give back 8.1$.

The remaining is 72.9$, this the remaining money you owe him after three months.

Answer 2

The logic is something like this:

Loan = $n
Payback amount #1 = 90% of $n
Update $n
Repeat

Answer 3

Bro I want Source Code