Question

777×5+999×7+222用简便方法计算

Answer 1

7*(111*5+999)+222
=7*(111*5+111*9)+111*2
=7*111*14+111*2
=111*(7*14+2)
=111*(7*7*2+2)
=111*2*(7*7+1)
=111*2*50
=11100