Question

7.2*4.6+46*0.28和9.8*3.6+7.2*0.1的简便计算

小学5年级数学评价手册上的第57页第4题，我先申明我没打错一个数字哦

Answer 1

7.2*4.6+46*0.28
=0.72*46+46*0.28
=46（0.72+0.28）
=46*1
=46

9.8*3.6+7.2*0.1
=9.8*3.6+3.6*0.2
=3.6（9.8+0.2）
=3.6*1
=3.6

Answer 2

7.2*4.6+46*0.28=7.2*4.6+4.6*2.8=(7.2+2.8)*4.6=10*4.6=46
9.8*3.6+7.2*0.1=9.8*3.6+3.6*0.2=(9.8+0.2)*3.6=10*3.6=36

Answer 3

1) (7.2/10)*(4.6*10)+46*0.28
=0.72*46+46*0.28
=46*(0.72+0.28)
=46*1
=46
2) 9.8*3.6+(7.2/2)*(0.1*2)
=3.6*(9.8+0.2)
=3.6*10
=36