A magician has a top hat with 20 red marbles and a top hat with 30 blue marbles. If he takes away 3 red marbles and four times as many blue marbles as red marbles (without looking), how many marbles in total does he have left?
How many red marbles did the magician have? ** He had 20 red marbles and took away 3 leaving 20-3 = <<20-3=17>>17 red marbles
How many blue marbles did the magician take? ** He took 4 times as many blue marbles as red marbles which is 4*3 = <<4*3=12>>12 blue marbles
How many blue marbles did the magician take? ** He took 12 blue marbles from 30 leaving 30-12 = 18 blue marbles
How many marbles does the magician have left? ** He now has 17+18 = <<17+18=35>>35 marbles left
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