9+99+999+9999+99999+999999+9999999+99999999=( )

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9+99+999+9999+99999+999999+9999999+99999999=( )

9+99+999+9999+99999+999999+9999999+99999999=( )
9+99+999+9999+99999+999999+9999999+99999999=( )

9+99+999+9999+99999+999999+9999999+99999999=( )
9+99+999+9999+99999+999999+9999999+99999999+999999999
=10-1+100-1+1000-1+10000-1+……+1000000000-1
=1111111101

=(10-1)+(100-1)+(1000-1)+(10000-1)+(100000-1)+(1000000-1)+(10000000-1)+(100000000-1)
=111111110-8
=111111102