Multiplying with response values and returning total in mail template

[rotaral...@gmail.com]

Hi,

I'm trying to multiply some responses with a fixed value in order to calculate a total 'price'.

This is my current mail template for now.
Currently, I only got the response fields like

${amount of x}
${amount of y}

and I'd like to have:

Total1 = ${amount of x} x 50

Total2 = ${amount of y} x 20
.. etc.

Is this possible through html?
Can I use the confirmation add-on for this?

Thanks

Kind regards
Arthur