In Pluto if I try to include an interpolated value in the markdown string, it renders the string without interpolating the value.

I'd like the string to render as: My variable's value is: 10
In Pluto if I try to include an interpolated value in the markdown string, it renders the string without interpolating the value.

I'd like the string to render as: My variable's value is: 10
Markdown itself isn't intended to interpolate variables. You may use Markdown.parse instead of md"" literal. This allows the string to interpolate the variables before passing to the Markdown parser.
Markdown.parse("""
My variable's value is: `$x`.
""")