Amazon Area Manager interview questions

Standard questions, give me a time when you had to overcome an obstacle and what steps did you use. Also one math question which I totally suck at math unless I have a chance to study. Word problem, calculate how many shipments per week given so many work hours with so many employees. After failing the math question she gave me another one which again I didn't get. Note to interviewer, if I didn't get the first one right, obviously I am going to have a hard time with the next one.