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

### Instruction:
 Trey有Kris的7倍多的乌龟。Kris有Kristen的四分之一的乌龟。如果Kristen有12只乌龟，Trey比Kristen多几只乌龟？


### Response:
 Kris有12/4 = <<12/4=3>>3只乌龟。
Trey有3*7 = <<3*7=21>>21只乌龟。
Trey比Kristen多9只乌龟。