We know that every 15 mins the Ferris wheel can accommodate 45 people. So the first thing you want to do is find out how many people the Ferris wheel accommodates in 1 hour. Your going to want to multiply 45 by 4 as there is 4 sets of 15 in an hour, 45x4=180. Now we know the rate per hour is 180 we can just multiply 180 by 4 because it's asking for how many people could ride in 4 hours