1) -0,25-3 1/2=-25/100-7/2= -25/100-350/100=-375/100= -15/4= -3 /34= -3,75
2) -9 1/4-0,75=-37/4-75/100= -925/100-75/100= -1000/100=-10
3) -3-2 3/5= -3-13/5=-15/5-13/5= -28/5= -5 3/5=-5,6
4) -27-5 9/20= -27-109/20= -540/20-109/20= -649/20= -32 9/20= -32,45