The volume of a right circular cone increased by a factor of 25. If the height remained fixed, by what factor was the radius changed? A. 5 B. 25 C. 125 D. 225

Answer:Step-by-step explanation:The appropriate formula is V = (1/3)(base area)(height), or V = (1/3)πr²h.Then the larger cone volume is V2 = (1/3)πR²h, where h, (1/3), the same in as before but V is 25 times greater:25V = (1/3)πR²h, which is to be compared to V = (1/3)πr²h.  Forming a ratio:25V = (1/3)πR²h-------   --------------    V     (1/3)πr²hSimplifying;  25 = R²r², or 5 = R/r.  Thus, the new radius is 5 times the old one.  Answer A is correct