kula A ma objetosc 10 a kula B 80.ile razy jest wiekszy promien kuli B od promienia kuli A

V_A = 10 {4 \over 3} \cdot \pi \cdot {r_A}^3 = 10 {r_A}^3 = {30 \over 4 \pi} r_A = \sqrt[3]{30 \over 4 \pi} r_A = \sqrt[3]{15 \over 2 \pi} V_B = 80 {4 \over 3} \cdot \pi \cdot {r_B}^3 = 80 {r_B}^3 = {240 \over 4 \pi} r_B = \sqrt[3]{240 \over 4 \pi} r_B = \sqrt[3]{60 \over \pi} {r_B \over r_A} = {\sqrt[3]{60 \over \pi} \over \sqrt[3]{15 \over 2 \pi}} = \sqrt[3]{{60 \over \pi} \over {15 \over 2 \pi}} = \sqrt[3]{{60 \over \pi} \cdot {2 \pi \over 15}} = \sqrt[3]{120 \over 15} = \sqrt[3]{8} = 2