78*99怎样简便运算
问题描述:
78*99怎样简便运算
答
原式=78x(100-1)
=7800-78
=7722
答
78*99=78*(100-1)=78*100-78=7800-78=7722
答
78*(100-1)
=7800-78
=7722
答
78×99
=78×(100-1)
=78×100-78
=7800-78
=7722