Convert shortcode parameters to actionable floats

I’m trying to do some math from a nested shortcode. My code looks like

{{ with .Parent }}
{{ $blocks := (div 12 (.Get "columns")) }}
<div class = 'column col-lg-{{ with $blocks }}{{ . }}{{ else }}12{{ end }}'>
  {{ .Inner }}
{{ end }}

The columns value would be from the parent shortcode. My code fails so far because the input value of columns is a string. I would like to convert it into a float that would be work with the division operation.

You can use float: or int:

Thank you @pointyfar