Why isn’t there a commutative property for subtraction as well as for addition?

Do 12/14 and 8/10 have the same value? explain your answer.

During a bike challenge riders have to collect various colored ribbons each 1/2 mile they collect a red ribbon each eighth mile they collect a green ribbon and each quarter mile they collect a blue ribbion wich colors of ribion will be collected at the 3/4 markrer

The anwser cause i do not understand just plez