[tex]\sqrt[3]{27}=3[/tex]
[tex]\sqrt[3]{64}=4[/tex]
[tex]27<50<64\implies\sqrt[3]{27}=3<\sqrt[3]{50}<4=\sqrt[3]{64}[/tex]
which follows from the fact that [tex]\sqrt[3]x[/tex] is a monotonic function (but that may be more detail than is needed for this problem).
