Your speedometer reading is 63 mph, but your tires are larger than the original factory-installed tires. How fast is your SUV actually moving? The circumference of the factory-installed tires was 75.1 inches, but your current tires are 82.4 inches around.

Step-by-step explanation:

Let the speedometer reading is mph, perimeter of factory-installed tires is inches and perimeter of current tires is inches.

The speedometer reading, ,  is based on the number of actual revolution of tires in second, , and on the perimeter of installed tires, , as

Let be the actual speed of SUV having actual perimeter inches,

[from equation ]

So, from the given values, we have

mph

mph

Hence, the actual speed of the SUV is mph.