Question

32.1×9.9的简便运算？

32.6×2.9+3.26×71

Answer 1

32.1×9.9
=32.1x10-3.2x0.1
=321-0.32
=320.68
第二题
32.6×2.9+3.26×71
=32.6x(2.9+7.1)
=32.6x10
=326

Answer 2

32.6×2.9+3.26×71
=32.6×2.9+32.6×7.1
=32.6×（2.9+7.1）
=32.6×10
=326

Answer 3

因为9.9=10-0.1，所以原式等于32.1×（10-0.1）运用乘法分配律就是有32.1×10-32.1×0.1=317.79

Answer 4

32.1×9.9
＝32.1×10-32.1×0.1
＝321-3.21
＝317.79

Answer 5

32.1x9.9＝32.1x（10一0.1）
＝32.1x10一32.1x0.1
＝321一3.21
＝317.79