20% off. According to a search on McDonald's official website, Maili is the collective name for McDonald's consumers. McDonald's group meal discounts will be synchronized with text messages sent to Maili's mobile phones when updated. So Mai Li knows that it is best to get a 20% discount on group meals. McDonald's is a large multinational restaurant chain in the world. McDonald's revenue in 2022 was US$23.18 billion. It was founded in Chicago, USA in 1955 and has approximately 30,000 branches around the world.