Solution: The volume of a hemisphere is $ \frac23\pi r^3 = \frac23\pi (2x)^3 = \frac163\pi x^3 $. The cylinder's volume is $ \pi r^2 h = \pi x^2 \cdot 4x = 4\pi x^3 $. The ratio is $ \frac\frac163\pi x^34\pi x^3 = \frac163 \div 4 = \frac43 $. Thus, the ratio is $ \boxed\dfrac43 $. - Nelissen Grade advocaten