Provide a step by step solution for the following math problem: Lauren is a cartoonist.  She can draw 5 large-sized picture scenes per day, or she can draw 6 medium-sized picture scenes per day, or she can draw 7 small-sized picture scenes per day.  She was hired for a big project to create 45 large-sized picture scenes, 36 medium-sized picture scenes, and 49 small-sized picture scenes.  How many days will it take for her to create all of the picture scenes?