Verified answer

1- 2/10 + 2/10 + 5/10 = 9/10

2- 2/12 + 6/12 + 6/12 = 14/12 simplifico 7/6

1/5+2/10+1/2= 2+2+5 /

------------=11/10

10

2+6+6

1/6+2/4+1/2=-------------= 14/12 simplificamos 7/6

12

1)mmc=10

(2+2-5)/10=-1/10

2)mmc=12

(2+6+6)/12=14/12

14/12=7/6