99×78用简便方法怎么计算

Question

如题所述

Answer 1

计算：
99×78
=（100-1）×78
=100×78-1×78
=7722

Answer 2

99×78用
=(100-1)x78
=7800-78
=7722

Answer 3

99x78
=（100-1）x78
=100x78-78x1
=7800-78
=7722

Answer 4

＝（100-1）x78
＝100x78-78
＝7800-78
＝7722

Answer 5

99×78=（100-1）×78=100×78-1×78=7800-78=7722