Broken Elevator

Question: An apartment building has 9 residential floors and an underground parking lot. There are 10 flights of stairs. The first flight between the parking lot and the first floor has 5 steps. Each flight after that has has one more step than the previous flight. One day the elevator was out of order. If someone had to walk from the parking lot to the 9th floor or vice versa, how may steps would they walk up/down?