Question

пж помогите
найдите сумму или разность
б)5/7-1/14,
7/20+2/3,
3 1/30-5 7/90

Answer 1

б) 5/7-1/14=
10/14-1/14=

=9/14

7/20+2/3=
=21/60+40/60=
=61/60=

=1 1/60

3 1/30-5 7/90=
=3 3/90-5 7/90=
=-(5 7/90-3 3/90)=
=-2 4/90=

=-2 2/45