Question

用简便方法计算下列各题，我很急，在线等，谢谢！

1.8×19.2-3.6×4.6
3.2×1.85+1.6×16.3
6.38×9.9+33×3.62×0.3

Answer 1

您好：

1.8×19.2-3.6×4.6
=1.8x19.2-1.8x2x4.6
=1.8x(19.2-9.2)
=1.8x10
=18

3.2×1.85+1.6×16.3
=1.6x2x1.85+1.6x16.3
=1.6x(3.7+16.3)
=1.6x20
=32

6.38×9.9+33×3.62×0.3
=6.38x9.9+9.9x3.62
=9.9x(6.38+3.62)
=9.9x10
=99

不明白，可以追问
如有帮助，记得采纳，谢谢
祝学习进步！

Answer 2

1.8×19.2-3.6×4.6
=3.6×9.6-3.6×4.6
=3.6×(9.6-4.6)
=18

3.2×1.85+1.6×16.3
=1.6×3.7+1.6×16.3
=1.6×(3.7+16.3)
=1.6×20
=32

6.38×9.9+33×3.62×0.3
=6.38×9.9+9.9×3.62
=9.9×(6.38+3.62)
=99

Answer 3

同志您好:
第一题
3.6=1.8*2
所以可以写成
1.8*19.2-1.8*2*4.6
=1.8*19.2-1.8*9.2 (2*4.6=9.2)
=1.8*(19.2-9.2) (结合律)
=1.8*10
=18
第二题
3.2=1.6*2
所以可以写成 (与上题同理哦)
1.6*2*1.85+1.6*16.3
=1.6*3.7+1.6*16.3
=1.6*(3.7+16.3)
=1.6*20
=32
最后一题了,亲!!!!
33*0.3=9.9
所以可以写成 (原理与上面两题相反哦...)
6.38*9.9+3.62*9.9
=9.9*(6.38+3.62)
=9.9*10=99

此三类题原理基本相同,找出公因式,并提取合并,从而化简算式,巧妙解题.......
希望能帮到你....

Answer 4

1.8×19.2-3.6×4.6
＝1.8×19.2-1.8×2×4.6

＝1.8×﹙19.2-2×4.6﹚
＝1.8×10

＝18

3.2×1.85+1.6×16.3
＝1.6×2×1.85+1.6×16.3

＝1.6×﹙2×1.85＋16.3﹚

＝1.6×20

＝32

6.38×9.9+33×3.62×0.3

＝6.38×9.9+33×0.3×3.62

＝6.38×9.9＋9.9×3.62

＝9.9×﹙6.38＋3.62﹚

＝9.9×10

＝99

Answer 5

1.8×19.2-3.6×4.6
=1.8x19.2-1.8x2x4.6
=1.8x(19.2-9.2)
=1.8x10
=18

3.2×1.85 1.6×16.3
=1.6x2x1.85 1.6x16.3
=1.6x(3.7 16.3)
=1.6x20
=32

6.38×9.9 33×3.62×0.3
=6.38x9.9 9.9x3.62
=9.9x(6.38 3.62)
=9.9x10
=99

追问

你空的地方是+号吗