conversations.from: human
conversations.value: Provide a step by step solution for the following math problem: 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?
conversations.from: assistant
conversations.value: Fred has 38/2 = 19 green marbles.
  Fred has 63-38-19 = 6 dark blue marbles.