#4# over #3# can be written as #4/3#
#4# over #3# out of #60# can be written as #4/3 div 60#
dividing by #60# is the same as multiplying by #1#, then dividing by #60#. therefore dividing by #60# is the same as multiplying by #1/60#.
#4/3 div 60# is the same as #4/3 * 1/60#
#4/3 * 1/60 = (4 * 1) / (3 * 60)#
#= 4/180 = 1/45#