You can use dimensional analysis to answer this question.
[tex]=\frac{473\ m}{1\ s}[/tex] × [tex]\frac{1\ km}{1000\ m}[/tex] × [tex]\frac{60\ s}{1\ min}[/tex] × [tex]\frac{60\ min}{1\ hour}[/tex]
= 1702.8 km/h
If you did this correctly, all your units should cancel out, leaving you with km/h