Typically, the maximum size of the hoop is 56.5’’, and two basketballs can fit into it unless the circumference of both of the basketballs remains lower than 56’’. The diameter of the rim of the Basketball is 18’’ with a circumference of 56.5’’. So, technically it would not be possible for two basketballs of 7 and 6 size to enter the hoop; however, there will not be any resistance if the sizes of basketballs are 5 and 7.