=35.4+(4.4+5.6)=35.4+10=45.4
35.6+4.4-5.6=35.6-5.6+4.4=30+4.4=34.4
35.6+4.4-5.6=(35.6-5.6)+4.4=30+4.4=34.4希望能帮到你!