如题所述
第1个回答 2020-08-06
7.2+2.8×4.5
=7.2+(3×4.5-0.2×4.5)
=7.2+13.5-0.9
=19.8
=7.2+(3×4.5-0.2×4.5)
=7.2+13.5-0.9
=19.8
第2个回答 2020-08-06
7.2+2.8*4.5
=7.2+(3-0.2)*4.5
=7.2+3*4.5-0.2*4.5
=7.2+13.5-0.9
=20.7-0.9
=19.8本回答被网友采纳
=7.2+(3-0.2)*4.5
=7.2+3*4.5-0.2*4.5
=7.2+13.5-0.9
=20.7-0.9
=19.8本回答被网友采纳
第3个回答 2020-08-06