<span>The lowest common factor of 7 and 18 is 126 (this is a number that both 7 and 18 multiply into, in fact by each other). This means the 126th person will be the first to get both coupons.</span>
Step-by-step explanation:
We have given that,
The inner radius of a bicycle wheel is 12 inches.
It is required to find the expression to find the inside circumference of this wheel.
The outer surface of the wheel is equal to its circumference. It is given by :

r is radius of wheel

This is the required explanation.
B. 12 units because when you add the lengths together you get 12