The length of Alex's yard is 30/6=<<30/6=5>>5 yards.

The length of Derrick's yard is 5*2=<<5*2=10>>10 yards.

# Answer

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<|im_start|>user
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?
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user
10
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?
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