Mike buys a ring for his finacee by paying $30 per month for one year. If the interest rate is 10% per year, what was the original price of the ring?
Here are the compound interest formulas my teacher gave us to use for this problem. we are suppose to pick the right one but I am not sure which one to use.
monthly payment-> (A*R*(1+R)^N)/((1+R)^N-1)
ordinary annuity-> A=P(((1+R)^n-1)/(R))
annuity due-> A=P(((1+R)^n-1)/(R)) (1+R)