Mary would like to plant grass in her backyard. Her backyard is a rectangle that measures 10 yds by 8 yds. In the middle of her backyard is a circular swimming pool that has a diameter of 5 yds. What is the area to be planted with grass to the nearest tenth of a square yard?

The area to be planted with grass can be found by subtracting the area of the circular swimming pool from the total area of the rectangle. The area of the rectangle is calculated by multiplying the length and width, which gives us 10 yds * 8 yds = 80 yd2. The area of the circular swimming pool is calculated by using the formula for the area of a circle, which is π * (radius)2. The radius of the circular swimming pool is half of the diameter, so it is 5 yds / 2 = 2.5 yds. Plugging this into the formula, we get π * (2.5 yds)2 = 19.63 yd2. Subtracting this from the total area of the rectangle, we get 80 yd2 - 19.63 yd2 = 60.37 yd2. Rounding to the nearest tenth, the area to be planted with grass is approximately 60.4 yd2. Therefore, the correct answer is C.