1) (8/5+9/5)*1/2 = 8/10+9/10=0,8+0,9=1,7
2) (60-68/15)/(11/5)=(60-68/15)*5/11=300/11-340/165=4500/165-340/165=4160/165=832/35
3)(5/4+1/6)*12/5=(15/12+2/12)*12/5=17/12*12/5=17/5=3,4
4)(37/5-7/3)/(23/3)=(111/15-35/15)*3/23=76/15*3/23=76/5*1/23=76/115
5)(7/3+1/4)*12/100=(28/12+3/12)*3/25=31/12*3/25=31/4*1/25=31/100=0,31
6)(76/100-19/4)/(19/10)=(76/100-475/100)*(10/19)=-399/100*10/19=-399/10*1/19=-399/190=-2,1