553.1. (5/6+8/9)-1,5=2/9
5/6+8/9=15/18+16/18=31/18
31/18-1,5=31/18-3/2=31/18-27/18=4/18=2/9
2. (6 1/15-7 1/3)+8,3=7 1/30
6 1/15-7 1/3=6 1/15-7 5/15=-19/15
-11/15+8,3=83/10-19/15=249/30-38/30=211/30=7 1/30
554.1. (-96-86)-22,2=-182-22,2=-204,2
2. (40,3-51,22)-(-4,38)=-10,92+4,38=-6,54
3. (-91,49+80,09)-7,4=-11,4-7,4=-18,8