I thought there wer 1000 as well... if that is the case.Isn't there 1000 boxes of Boris? Making 2300 total?
2300 / 13 = 1 in 176.9 chance of getting a ticket
If you use your numbers:
1950 / 13 = 1 in 150 chance of getting a ticket
1 in 176.92 of getting a ticket...
1 in 2300 of getting a Ducati!