You are planning to take on a part time job as a waiter at a local restaurant. during your interview, the boss told you that their best waitress, betty, made an average of $70 a night in tips last week. however, when you asked betty about this, she said she made an average of only $50 per night last week. she provides you with a copy of her nightly tip amounts from last week: day tip amount sunday $50 monday $45 wednesday $48 friday $125 saturday $85 calculate the mean and median tip amount. which value did betty's boss use to describe the average tip? which did betty use?