Your answer will be 9 and a half or 10 minutes.
Why? Well, Follow the steps below:
First, you have 4 minutes per 5 baskets. 5+5=10, so 4+4=8. He's tracked 10 baskets so far.
Now, you have 10 baskets. You're looking for 12. 5-3=2.
Then, for 2 baskets, it should've been a half of a minute to one minute.
Put it together, and you've got 9 1/2 to 10 minutes.
I hope this helps!