At the end of each working day, a sales assistant is paid for the services the greater of either $20 per hour or, alternatively, a lesser hourly rate of $5 per hour plus 15% commission on their total net sales. For example, a sales assistant who, in 7 hours, makes total net sales of $1000 will earn $185 - if no sales were made, earnings for the same 7 hour period would instead become $140.