When something is deducible, it follows logically from a general principle, meaning you can figure it out by working through it. Your school admits only geniuses? You've been admitted to your school? It's deducible that you're a genius.
Something deducible is able to be deduced. Both words include the Latin roots meaning "from" (de-) and "lead" (ducere). So the deducible conclusion is one you're led to — by means of reasoning — from a general principle. You might learn from experts the general principle that all goats love to eat grass. You've got a pet goat in your backyard. It's deducible that you'd better find some grass for your goat.