Fred has 38 red marbles, half as many green ones, and the rest are dark blue. If he has 63 marbles, how many of them are dark blue?
How many green marbles does Fred have? ** Fred has 38/2 = <<38/2=19>>19 green marbles.
How many dark blue marbles does Fred have? ** Fred has 63-38-19 = <<63-38-19=6>>6 dark blue marbles.
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