18.25-4又2/5+(+18又1/4)+(-4.4) -(-1/2)+(-1/3)-(1/9) 3/7×5/13-3/7×(-11/13)-3/7×3/13
问题描述:
18.25-4又2/5+(+18又1/4)+(-4.4) -(-1/2)+(-1/3)-(1/9) 3/7×5/13-3/7×(-11/13)-3/7×3/13
答
18.25-4又2/5+(+18又1/4)+(-4.4)=18.25-4.4+18.25-4.4=36.5-8.8=27.7 -(-1/2)+(-1/3)-(1/9)=1/2-1/3-1/9=1/6-1/9=1/18 3/7×5/13-3/7×(-11/13)-3/7×3/13=3/7x(5+11-3)/13=3/7