Pune in casete semnele operatiilor pt a obtine repari adevarate:100-80_40_72_3=74

Răspuns :

 (100-(80:40))-(72:3)=
=(100-2)-24
=98-24
=74
-----------------------------
  100-80:40-72:3=
 =100-2-24
 =98-24
 =74