a) -4/3×1/5×15=-4/15×15=-4
b) 1/5×2:2/5=2/5×5/2=1
c) 1 intreg 2/3=5/3
0,3=3/10
2/3-3/10×3/5=2/3-9/50 amplificãm pe 2/3 cu 50 si pe 9/50 cu 3= 100/50-27/50=73/50
d) 4 întregi 1/3=13/3
2 intregi 5/7=19/7
(13/3-19/7-13/3):19/7=-19/7×7/19=-1
e) -1,8:3/5=-9/5:3/5=-9/5×5/3=-3
-1,8=-18/10=-9/5