A large PC manufacturing unit has 1000 CPU (central processing units) with speed 2.6 GHz. Each unit has been labeled with a number from 1 to 1000. The same manufacturer has also 1750 CPU with speed 3.0 GHz. Each of those units has been labeled with a number from 1 to 1750. We choose randomly a CPU, without knowing its speed, and observe that the number on its label is divisible by 6. What is the probability that it is also divisible by 8?