Example Output

Here is a sample run of the above (correct) program:

You toss a 11
You toss a 8
You toss a 6
You toss a 5
You toss a 5
You toss a 5
You toss a 6
You toss a 6
You toss a 6
You toss a 12
You toss a 4
You toss a 5 Exception in thread "main" . . .

Here is a sample run of a program that (incorrectly) uses (rand.nextInt(11)+2):

You toss a 6
You toss a 10
You toss a 11
You toss a 4
You toss a 6
You toss a 5
You toss a 11
You toss a 9
You toss a 7
You toss a 2
You toss a 4
You toss a 3 Exception in thread "main" . . .

With such a small sample, you can't tell for sure that something is wrong, but you might be suspicious. To confirm your suspicions, gather much more data, then count the number of times each outcome occurs and check that the results match what you expect. This is part of what is studied in a probablility and statistics course.