Answer:
3.15 ft
Step-by-step explanation:
V
Volume of a cylinder: πr²h. Solving for r², we get r² = ---------
πh
Here, we get r² = (117.1 ft³) / (3.14·15 ft) = 2.48 ft² and r = √(2.48 ft²), or
1.58 ft, so that the diameter is 2r, or 3.15 ft
The diameter of the base of the cylinder is 3.15 ft.