Final answer:
Vita can center the towel bar on her 27 1/2-inch wide door by ensuring it is 9.5 inches long. This is done by deducting the combined distances from the ends of the towel bar to the door edges (18 inches) from the total width of the door.
Step-by-step explanation:
Vita wants to find the length of the towel bar that she wants to center on a door that is 27 1/2 inches wide, with the distance from each end of the towel bar to the end of the door being 9 inches. To solve for the length of the towel bar, we denote the length of the towel bar by x. Then, we can set up an equation where the sum of the distances from both ends of the towel bar to the door edges and the length of the towel bar itself equals the width of the door.
The equation will be:
9 inches + x + 9 inches = 27 1/2 inches
We combine the known distances to simplify the equation:
18 inches + x = 27 1/2 inches
To find x, we subtract 18 inches from both sides of the equation:
x = 27 1/2 inches - 18 inches
Converting 27 1/2 inches to a decimal, we have 27.5 inches. Thus:
x = 27.5 inches - 18 inches
x = 9.5 inches
Therefore, the length of Vita's towel bar should be 9.5 inches long to be centered on her 27 1/2-inch wide door.