1/2-0,3= 1/2 - 3/10 = 5/10 - 3/10 = 2/10 = 1/5,
-2/3+0,1 = -2/3 + 1/10 = -20/30 + 3/30 = -17/30
-2/7*1,4 = -2/7 * 14/10 = -2/5
0,48:(-12/13) = 48/100 * ( -13/12) = -52/100 = -13/25
-2 1/4+1,7 = -2 1/4 + 1 7/10 = -2 5/20 + 1 14/20 = -11/20
1 1/3-3,3 = 1 1/3 - 3 3/10 = 1 10/30 - 3 9/30 = -1 29/30
1 1/5*(-2,5) = 1 1/5 * (-2 5/10) = 6/5 * ( -5/2) = -3
-3,25:2 1/2 = -3 1/4 : 2 1/2 = -13/4 * 2/5 = -13/10 = -1 3/10