The amount of a chemical in the body decreases by 23% every hour. there was 100 MG at the start. Write the exponential equation that gives the amount at time T

Raymond just got done jumping at super bounce trampoline center. the total cost of his session was $43.25 . he had to pay a $7 entrance fee and $1.25 for every minute he was on the trampoline. write an equation to determine the number of minutes (t) that raymond was on the trampoline.