Răspuns :
13) a)
[tex]\frac{8}{9}+\frac{14}{27}+\frac{1}{9}=\frac{24+14+3}{27}=\frac{41}{27} \\\\\frac{3}{17}+\frac{8}{102}+\frac{14}{17}=\frac{18+8+84}{102}=\frac{110}{102}=\frac{55}{51}\\[/tex]
1/33 + 3/11 + 2/11 = (1+9+6)/33 = 16/33
2/5 + 1/20 + 4/5 = (8+1+16)/20 = 25/20 = 5/4