Revolutions - Wheel / Partial Solution

Number of inches in 10 miles =5280*10*12=633,600
Using your figure for diameter 633,600/88=7,200 revolutions in 10 miles per 1 hour.
Number of revolutions in 1 minute =7,200/60=120

I think your initial assignment of N is confusing.

"I think your initial assignment of N is confusing. "

What should I have used ? Thanks.

I have a follow-up:

Here is another partial solution - pi x 28 x n x 60 / 5280 x 12
pi x 28 x n x 60 / 5820 x 12 = 10
pi x 7 x n / 88 x 3 = 10
n = 10 x 88 x 3 / pi x 7
10 x 88 / 7 = 130
n = 120

Please explain these steps.