Question

999ⅹ333ⅹ666-111的简便计算？

Answer 1

9×111×3×111×6×111-111=9×3×6×111³-111=221556222-111=221556111

Answer 2

解:999×333×666-111
＝（1000-1）×221778-111
＝221778000-221778-111
＝221556222-111
＝221556111。