Final answer:
To cover the table and hang appropriately, the tablecloth should have a diameter of 90 inches, calculated by adding the table's radius (20 inches) to the length from the table's edge to 5 inches above the floor (25 inches) and then doubling it.
Step-by-step explanation:
To calculate the correct size of the tablecloth needed to cover a circular table and hang a specific distance above the floor, we need to consider the radius of the table and the distance from the table's edge to the desired ending point of the tablecloth.
The table has a radius of 20 inches, and it is 30 inches above the floor. If the tablecloth needs to hang 5 inches above the floor, the length of the tablecloth from the table's edge to the floor is 30 inches - 5 inches = 25 inches.
Therefore, the total radius of the tablecloth must be the table's radius plus this length, which is 20 inches + 25 inches = 45 inches. To cover the circular table, the diameter of the tablecloth must be twice this radius, so we calculate 45 inches * 2 = 90 inches.