Final answer:
The average speed of the Ferris wheel is 8.5 mph, which is calculated by dividing the circumference in miles by the time in hours.
Step-by-step explanation:
To calculate the average speed of the Ferris wheel in miles per hour, we'll use the fact that speed equals distance divided by time. First, we need to convert the circumference from feet to miles. There are 5280 feet in a mile, so the Ferris wheel's circumference in miles is 624 feet / 5280 feet/mile = 0.11818 miles (rounded to the fifth decimal). Knowing that a trip around takes 50 seconds, we need to convert this time into hours. There are 3600 seconds in an hour, so 50 seconds is equal to 50 seconds / 3600 seconds/hour = 0.01389 hours (rounded to the fifth decimal).
Now we divide the distance by the time to find the speed in miles per hour. The speed is 0.11818 miles / 0.01389 hours = 8.5 mph (rounded to the nearest tenth).
Therefore, the correct answer is none of the options A) 6.3 mph, B) 4.2 mph, C) 9.6 mph, or D) 7.8 mph. The average speed of the Ferris wheel is 8.5 mph.