1/5-2/15; 2 1/5*5/8; 4,3+0,12; 3,6/7,2; 0,5+1/3; 2 1/4 / 0,3; (4/3)*(-2);

1/5-2/15=3/15-2/15=1/15
2 1/5*5/8=11/5*5/8=11/8=2 3/8
4,3+0,12=43/10+12/100=430/100+12/100=442/100=4 42/100=4 21/50
3,6:7,2=36/10:72/100=36/10*10/72=1/2
0,5+1/3=5/10+1/3=15/30+10/30=25/30=5/6
2 1/4:0,3=9/4:3/10=9/4*10/3=15/2=7 1/2
4/3*(-2)=-8/3=-2 2/3