now, keeping in mind that 1 degree has 60 minutes, and that 1 minute has 60 seconds and therefore there are 60*60 seconds in 1 degree, or 3600 seconds.
72°22'30", has 72 degrees, plus 22 minutes and 30 seconds.
or 72 degrees plus 22/60 degrees plus 30/3600 degrees.
[tex] \bf 72+\boxed{\cfrac{22}{60}+\cfrac{30}{3600}}\implies \cfrac{11}{30}+\cfrac{1}{120}\implies \stackrel{\textit{LCD of 120}}{\cfrac{44+1}{120}}\implies \cfrac{45}{120}\implies \cfrac{3}{8}\\\\[-0.35em]
\rule{34em}{0.25pt}\\\\
72+\cfrac{3}{8}\implies 72\frac{3}{8}^o [/tex]
