Question

78×99+78（竖式 简便运算）

Answer 1

=78*99+78*1
=（99+1）*78
=100*78
=7800

Answer 2

Answer 3

Answer 4

78×99+78
=78×（99+1）
=78×100
=7800

Answer 5

78x99+78
=78(99+1)
=7800