Ludo bought 1/4 more marbles than Wolfgang, which is 1/4 * 16 marbles = <<1/4*16=4>>4 marbles
The total number of marbles that Ludo bought is 16 marbles + 4 marbles = <<16+4=20>>20 marbles
Wolfgang and Ludo purchased a total of 20 marbles + 16 marbles = <<20+16=36>>36 marbles.
If Michael bought 2/3 times the total number of marbles bought by Wolfgang and Ludo, he bought 2/3 * 36 marbles = <<2/3*36=24>>24 marbles.
The three friends purchased a total of 24 marbles + 36 marbles = <<24+36=60>>60 marbles.
When they shared the marbles equally, each got 60 marbles / 3 people = <<60/3=20>>20 marbles/person.
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