27.9+3.6*2.5/0.4
问题描述：
27.9+3.6*2.5/0.4
答
27.9+3.6*2.5/0.4
=3.1×9+9×2.5
=（3.1+2.5）×9
=5.6×（10-1）
=56-5.6
=50.4不大明白呀27.9+3.6*2.5/0.4 =3.1×9+3.6÷0.4×2.5 =3.1×9+9×2.5 =（3.1+2.5）×9 =5.6×（10-1） =56-5.6 =50.4