Răspuns:
1. se aduce la acelasi numitor, inmultesti a doua fractie cu 3
(1 +2*3)/9= 7/9
2. 1*4/ 2*9 + 2/5= 2/9+2/5 = (2*5+ 2*9)/5*9= se aduce la acelasi numitor 40
(10+18)/40= 28/40= 7/10 (se simplifica adica se imparte prin 4 fiecare termen
3. 3/24 +5/8= 1/8+ 5/8= 6/8= 3/4 ( se simplifica prin 2)
4. 1/5 : 1/16 =16/5
5. 2/3+ 1/72= (2*24 +1)/72= 49/72
6. 3/5 x5/5= 3/5x1= 3/5
7. 1/8 x5/1 +1/2 = 5/8 +1/2 = (5+ 4)/8= 9/8