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Slide Rule
(sh.itjust.works)
Be sure to follow the rule before you head out.
Rule: You must post before you leave.
I think what you really want is nomogram, which is like a non-moving sliderule in the form of a graph, which is great for "If I have X of thing A, and Y of thing B, how much of thing C do I get/need?" questions like baking ratios.
Unforuntately, I can't really find an nomogram generators online that I can get to work (though that might be a me-problem, and not a website problem)