Question

1.-8-(-12)-(-7)+12-20
2.2 3/4-(-1 1/2)+(-3 5/6)​

Answer 1

1.-8-(-12)-(-7)+12-20=-8+12+7+12-20=3

2.2 3/4-(-1 1/2)+(-3 5/6)=2 3/4+1 1/2- 3 5/6=

=11/4+3/2-23/6=общий знаменатель 12=

=(11*3+3*6-23*2)/12=5/12