Mission 1: Easy completion
Start the game with five of each flavor. Find out the most popular one and purchase those. Raise your prices to 50. Once your rating is 3%, raise the prices to 60 or 70. At a 7% rating, raise prices again to 80 or 90. Monitor your flavors constantly until you reach a 10% rating.
Mission 2: Easy completion
Try to raise your rating as much as possible before hitting your goal. To reach your goal, raise your prices to 300 and purchase the most expensive ice creams (the newly unlocked ones) then alternate between the most populated areas.
