Ruby on Rails

I don't know the exact set up but it's a float - the sum either needs to add up to 1 or 100 depending on how i set up the recipes.  The only reason I'm doing this is I need a beginner project to work on and this is something i know - and the blog idea keeps bogging down.

After more thought - here's what ideally i think i would like to do.

Create a New Bulk - when ready click a button or link that says 'enter recipe'.

The new recipe page has an add ingredient button that by ajax adds another line to the 'recipe' div on the end - it draws ingredients (via ajax) from the ingredient database, there's an outer div that would sum all the ingredient quantities and not allow the submit button to work until it adds up to the right number.

Does that seem like the way to go about it?

(at this point - all ingredients would be in lbs)