8. Calculati
/=supra
(c nu trebuie si nu e scris)
a. (1/21+1/14)-(1/35-1/42)+(1/14-1/21)=
b.(4 1/6- 1 1/9)-(11/8-7/24)+(1/10+1/15)=
d.(7/9+17/10-1/18)-(13/27-1/18+7/9)+(1/10+1/15+1/9)=

7.Calculati
a.(7/9+17/6)-(5/6-1/18)=
b.(17/24+5/36)-(5/60-1/18)=
c.(4 7/9- 1 1/2)-(15/16-1/24)=
​