(1) 2.5x-4.8=5.22.5x=10x=4(2)=333.3×0.84-333.3×0.74=333.3×(0.84-0.74)=333.3×0.1=33.33(3)=(1+40)×40÷2=820
X等于433.3340除以2=20,20乘以20等于400,400+40等于440
1,写不清2.=333.3*3*0.28-333.3*2*0.37=333.3*(3*0.28-2*0.37)=33.333.=(1+40)*40/2=820