You receive 6,66 in the supermarket after buy something
depends on the range of values. If you purchased a $3.34 item and tendered a $10 bill, then the odds of getting $6.66 in change is 100%
If you tendered a $5 bill, the odds are zero.
Your lottery ticket has 666.
depends on the number of digits in the lottery number. If it has 12 digits, and you want the odds of getting 666 as three consecutive digits??
odds of any 3 digits being 666 is 1/1000. but there are 9 possible 3 digit positions in a 12 digit number, so the odds are 9/1000
In a state that has almost 1 million license plate number you see a car with the license plate ending in 666.
Depends on the state and how they arrange numbers and letters in the number. In my state, the odds are zero for older current plates and for current plates, which have numbers only in the last three places, the odds are 1/1000. IF I assume 90% of the cars have newer plates, the odds are 0.9/1000.
But they may not allow repeated digits. The algorithm the state used for picking numbers is not obvious.
Other states may be different.