Tessellate S.T.E.M.S - Computer Science - School - Set 3 - Problem 3

There are a total of 40 gold coins in four wooden boxes (but you do not know how many in each individual box).

For each box, you can ask for a number of coins from that box, of your choice. If there are at least that many coins in that box, then you get as many coins as you asked for. Otherwise, you get nothing from that box.

You must place all your demands simultaneuosly in the beginning.

What is the maximum number of coins that you can guarantee yourself to get?

(If many options are correct, choose the strongest one)

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This problem is a part of Tessellate S.T.E.M.S.