To my knowledge there isn't a simple straight forward way as that to select values from a number field:
However, you can:
1) Convert your "numeric field to text" - as you mentioned above
OR
Use Mod Calculations and calculate a new field which will determine whether or not your number ends in a 0.
i.e.
MOD ( "Elevation" , 10) = 0
What this simple calc does is it selects all the values in the elevation that are divisible by 10.
i.e. numbers ending in 0.
Cheers,
Nelson