How many bills would it take to make a stack 1 mile high?

To determine how many bills it would take to make a stack 1 mile high, we first need to know the thickness of a single bill, which is approximately 0.0043 inches. There are 63,360 inches in a mile, so dividing that by the thickness of a bill gives about 14,800,000 bills needed to reach a height of 1 mile.