Which equation models this problem? Susan paid $36.90 for nine washcloths. What is the unit price, p, per washcloth?
A36.90p = 9
Bp/9 = 36.90
Cp/36.90 = 9
D9p = 36.90
A36.90p = 9
Bp/9 = 36.90
Cp/36.90 = 9
D9p = 36.90