Răspuns
12.dupa rezolvarea parantezei se aduce la acelasi numitor comun
a) =6/8+1/4=3/4+1/4=4/4=1
c) =3/3-12/13=39/39-36/39=3/39=1/13
b) =13/6-1/7=91/42-6/42=85/42
d) =4/3-11/11=44/33-33/33=11/33=1/3
13. introducem intregii in fractie
a)44/7-29/7=15/7
b) 109/9-49/9=60/9=20/3
c) 44/5-16/5=28/5
d) 200/11-82/11=118/11