Converting data to KB, MB, GB

I have been trying to convert raw numbers in a file to KB, GB or MB. For ex


get-content c:\temp\numbers.txt | select -object Name, {$_.Somename.value.ToMB()}

the text file contain numbers of different sizes that were recorded from another sheet.

or I would really like to pipe it into something like this


  $_ | Select-Object Name, @{n='Count';e={ $Count }}, @{n='Size';e={
    If     ($Size -gt 1GB) { "$('{0:N2}' -f ($Size / 1Gb)) GB" }
    ElseIf ($Size -gt 1MB) { "$('{0:N2}' -f ($Size / 1Mb)) MB" }
    ElseIf ($Size -gt 1KB) { "$('{0:N2}' -f ($Size / 1Kb)) KB" }
    Else                   { "$Size b" } }}