The grounds at the nursing home where you are a custodian have two flower gardens. One garden is in the shape of a rectangle, and the other is in the shape of a circle. The rectangular garden has a length of 6.5 feet and a width of 3 feet. The circular garden has a radius of 2.25 feet. The box of plant food that you use indicates a coverage area of 600 square feet. About how many times can you use the plant food on the two gardens before you run out of plant food?

14
17
18
25
51