Mathematics for IGCSE & O level - Mensuration (Section 3 - No. 41)
If the volume of a cylinder is 100π cm³ and the height is 4 cm, what is the radius?
2.5 cm
5 cm
10 cm
25 cm
คำอธิบาย
Volume = πr²h, therefore r = √(Volume / πh). r= √(100π / 4π) = √25 = 5 cm