Below is an instruction that describes a task. Write a response that appropriately completes the request in Swahili. Please answer in Swahili.

### Instruction:
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?

### Response:
 Urefu wa shamba la Alex ni 30/6=<<30/6=5>>5 mita.
Urefu wa shamba la Derrick ni 5*2=<<5*2=10>>10 mita.