Question

用简便方法计算四年级下册答案？

Answer 1

注意乘法分配律，交换律和结合律的运用。

Answer 2

如果是数学的话，九九乘法表就是最简单的

Answer 3

46×17/45
=（45+1）×17/45
=45×17/45+1×17/45
=17+17/45
=17又17/45
3/5÷4/17+17/5×1/4
=3/5×17/4+17/4×1/5
=17/4×（3/5+1/5）
=17/4×4/5
=17/5
[5/3-（2/5+3/4）〕÷31/4

（5/7-5/21）÷1/42
=5/7×42-5/21×42
=30-10
=20
5/13+8/27×3/4+8/13
=5/13+8/13+8/27×3/4
=1+2/9
=1又2/9
3/16÷〔（5/9-1/6）÷7/9〕
=3/16÷〔5/9×9/7-1/6×9/7〕
=3/16÷〔5/7-3/14〕
=3/16÷1/2
=3/16×2/1
=3/8