conversations.from: human
conversations.value: Provide a step by step solution for the following math problem: Derrick measures the length of his yard. The length of Alex's yard is half the size of Derrick's and the length of Brianne's yard is 6 times the size of Alex's. If Brianne's yard is 30 yards long, how long is Derrick's yard, in yards?
conversations.from: assistant
conversations.value: The length of Alex's yard is 30/6=5 yards.
  The length of Derrick's yard is 5*2=10 yards.