Verified answer

Пошаговое объяснение:

7 4/15-2 3/4= 7 16/60 -2 45/60=

=6 60/60+16/60-2 45/60=

=(6-2)+(60/60+16/60-45/60)=

=4+(60+16-45)/60=4+31/60=4 31/60