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

### Instruction:
 Samantha’s last name has three fewer letters than Bobbie’s last name. If Bobbie took two letters off her last name, she would have a last name twice the length of Jamie’s. Jamie’s full name is Jamie Grey. How many letters are in Samantha’s last name?


### Response:
 Jamie的姓有4个字母，所以Bobbie的姓有4*2 +2 = <<4*2+2=10>>10个字母。
Samantha的姓比Bobbie的姓少3个字母，所以Samantha的姓有10 - 3 = <<10-3=7>>7个字母。