How to find the given value is char or numeric in the varchar type

Ex:

CREATE TABLE tbl_stumark(

      [rno] [numeric](10) NOT NULL,

[mark] [varchar](5) NULL

     

)

insert some values from the table then,

Select * from tbl_stumark

Rno    mark 

1          50

2          45

3          ab

4          60

5          23

select COUNT(*) from [tbl_stumark] where mark like '%[0-9]%'

O/p:

Count

  4