American Express Industrial Engineer interview questions

This was my first round interview. It was on a video call with two industrial engineers. Lasted about an hour and was a few behavioral along with some case questions

First round was a phone interview with one of their representatives. Mostly behavioral questions. Second round was an onsite interview with two other IE's. More technical questions with the last one being one that requires math and reasoning. They leave the room and let you solve it. Third round was another phone interview with two more IE's of varying experience. More behavioral questions.