Problem $6-21$ Calculating Number of Periods $[$LO$3]$

One of your customers is delinquent on his accounts payable balance. You$$ve mutually agreed to a repayment schedule of $$750$ per month. You will charge $2\mathrm{.}05$ percent per month interest on the overdue balance. If the current balance is $$19,500,$ how long will it take for the account to be paid off? $($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$