1.44÷(7.82×0.8+2.18×0.8)÷(1-0.75)=1.44÷｛（7.82+2.18）×0.8｝÷(1-0.75)=1.44÷8÷0.25=1.44÷（8×0.25）=1.44÷2=0.72
