I need a simple interest formula?

Question

Question 1) Jenny agrees to loan alice $2000 to alice as long as alice can repay the money to her as soon as possible as a lump-sum, including simple interest of 5% per month until it is repaid.

This is the table:

Month (n) 1 2 3 4 5 6
Repayment ($r) 2000 2100 2200 2300 2400 2500

and so-on, until month 12, which is 3200


The question is: Clearly state the equation for repayment (r) as a function of time (n)



Question 2) What is the formula for simple interest, and what is:
Pricipale x Rate x Time (is this simple interest, or is it SI = (PrT)/100?)

Answer 1

p = $2,000 + $100(n - 1)

edit:
The month 12 payment would be $3,100. In order for it to be $3,200, month 1 payment would have to be $2,100, and the formula would be
p = $2,000 + $100n
which is more "real world"

2) Principle x Rate x Time, but rate (r) is usually expressed in percent, and you have to convert to decimal by dividing by 100. That would make the two equations the same.

Answer 2

Question 1) Repayment formula would be r=P+(P*rate*n).

Question 2) see above. SI=Prn you are correct.