1)-4,75+(-2 1/4))+(-1 2/3-1 4/9)=?
2)11+(-3 1/5)+(-15)=?

1) -4,75+(-2 1/4))+(-1 2/3-1 4/9)=- 19/4- 2 1/4-(1 2/3+1 4/9)=- 19/4- 9/4-((1+1)+(2\3+4\9))=- 19/4- 9/4-(2+ 10/9)=- 19/4- 9/4-(2+1 1/9)=- 19/4- 9/4-(2+1+1/9)=     - 19/4- 9/4-(3+ 1/9)=- 19/4- 9/4+(-3 1/9)=- 19/4- 9/4- 28/9= -91/9

2)11+(-3 1/5)+(-15)=11-3 1/5-15=-4-3 1/5= -7 1/5