Answer: C. 6 bags
Explanation:
To solve this, you need to calculate the area of every shape in the garden and then sum them up.
Semi circle:
Area of semi-circle = (π * radius²) / 2
Radius = Diameter/ 2 = 18/2 = 9 feet
Area = (3.14 * 9²) / 2
= 127.17 ft²
Rectangle:
= Length * Width
= 18 * 8
= 144 ft²
Triangle
= 1/2 * base * height
= 1/2 * 18 * 18
= 162 ft²
Added up:
= 127.17 + 144 + 162
= 427.17 ft²
If each bag covers 75 ft² each, the number of bags needed is:
= Area to cover / Coverage per bag
= 427.17 / 75
= 5.7
= 6 bags