Answer:
APR = 669.17%
Step-by-step explanation:
Cash 4U is charging $55 in interest for 6 days, that means it is charging Bob $9.17 in interest per day which is equivalent to 1.8333% daily interest. If we want to determine the APR we just have to multiply the daily interest by 365 days = 1.8333% per day x 365 days = 669.17%