99+999+9999+99999
9999999999+999999999+99999999+99999+9999+999+99+9=?
9+99+999+9999
9×9+99×99+999×999+9999×9999+9999+999+99+9=?等于多少?
9999×999×99×9+1+11+111+1111=(
9又1/7+99又2/7+999又3/7+9999又4/7+99999又5/7+999999又6/7简算
(9999+9997+.+9001)-(1+3+.+999)
巧算 (1)5×999+5+99×7+7+3×9+3 = = = = = (2)99999+
99×99+199 999×999+1999 简算.
9+99+999+9999+9999+99999=?
用乘法分配律简便法计算:9+99+99+999+4
99+99×99+999×999×999等于=?用简便方法计算,
111+222+333+444+555+666+777+888++++++++++++++++++++++999=?