Scratch

Help! I've been working on a project for a while but I didn't want to use the variables that scratch has. So I calculated the percentage (for the project) and made four sets of three digits (sprites) so I could display the numbers from the variables. So far sometimes the sprites are accurate, other times they're off by 10% or 1% sometimes others. Any ideas on how to fix this would definitely be appreciated. Heres an example of what I tried: (the variable "one" is the number I want to display)

Tens place: (usually the one that messes up)

<switch to costume[(( (( <{ 1 }> <mod>100  )) / 10  ))

Hundreds place:(normally accurate)
(if)
<if><( (( <{ 1 }> </> 1 )) <=> 100 )>
<switch to costume[ 9          (the digit one)
<else>
<switch to costume[ 10        (the digit zero)

Ones place: (another normal mess up)

<switch to costume[ (( <{ 1 }> <mod> 10 ))

Note: I'm also placing this on advanced topics.