In a big box, there are marbles in 4 colors. Inside, there are 20 red marbles.  There are three times more green marbles than red.  Yellow marbles make up 20% of the green marbles. How many marbles are of a different color if the total of all marbles in the box is three times more than the number of green marbles?
Please reason step by step, and put your final answer within \boxed{}.
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