Internet casinos using Gamesys software offer a game called "Klub Keno." It is like 40-ball keno, except if the special "star ball" matches one of the player's picks, then the win is doubled.
Rules
The following are my understanding of the rules. I couldn't find the rules anywhere in writing so I had to go off of observation. The "star ball" sometimes doesn't have a star on it, which made this difficult. If these rules are in error, then I welcome correction.
There are 40 balls, numbered 1 to 40.
The player shall pick 3 to 10 numbers.
One of the 40 balls shall be randomly chosen as the "Star Ball."
The game shall draw 10 numbers randomly.
The player shall be paid according to how many of the random draw match his chosen numbers.
If the Star Ball is drawn and matches one of the player's picks, then any win shall be doubled.
The following table shows what each number of catches pays by the number of picks.
Pay TableExpand
Catch
Pick 3
Pick 4
Pick 5
Pick 6
Pick 7
Pick 8
Pick 9
Pick 10
3
4
5
6
7
8
9
10
0
1
2
3
2
1
1
3
40
4
3
2
1
1
1
4
130
20
4
5
5
2
1
5
450
80
50
8
5
5
6
1000
450
100
25
25
7
1300
800
700
450
8
8000
7000
2000
9
10000
8000
10
15000
Analysis
The following table shows the number of combinations for each number of picks and catches.
Combination TableExpand
Catch
Pick 3
Pick 4
Pick 5
Pick 6
Pick 7
Pick 8
Pick 9
Pick 10
0
4060
27405
142506
593775
2035800
5852925
14307150
30045015
1
4350
40600
274050
1425060
5937750
20358000
58529250
143071500
2
1350
19575
182700
1233225
6412770
26719875
91611000
263381625
3
120
3600
52200
487200
3288600
17100720
71253000
244296000
4
210
6300
91350
852600
5755050
29926260
124692750
5
252
7560
109620
1023120
6906060
35911512
6
210
6300
91350
852600
5755050
7
120
3600
52200
487200
8
45
1350
19575
9
10
300
10
1
Total
9880
91390
658008
3838380
18643560
76904685
273438880
847660528
The next table shows the probability, to six decimal points, for each number of picks and catches.
Probability TableExpand
Catch
Pick 3
Pick 4
Pick 5
Pick 6
Pick 7
Pick 8
Pick 9
Pick 10
0
0.410931
0.299869
0.216572
0.154694
0.109196
0.076106
0.052323
0.035445
1
0.440283
0.44425
0.416484
0.371266
0.318488
0.264717
0.214049
0.168784
2
0.136640
0.214192
0.277656
0.321288
0.343967
0.347441
0.335033
0.310716
3
0.012146
0.039392
0.07933
0.126929
0.176393
0.222363
0.260581
0.288200
4
0.002298
0.009574
0.023799
0.045732
0.074834
0.109444
0.147102
5
0.000383
0.00197
0.00588
0.013304
0.025256
0.042365
6
0.000055
0.000338
0.001188
0.003118
0.006789
7
0.000006
0.000047
0.000191
0.000575
8
0.000001
0.000005
0.000023
9
0.000000
0.000000
10
0.000000
Total
1.000000
1.000000
1.000000
1.000000
1.000000
1.000000
1.000000
1.000000
The next table shows the contribution to the return, to six decimal points, for each number of picks and catches. This table reflects the probability and effect of catching the Star Ball. The bottom row shows the total return for each number of picks.
Return TableExpand
Catch
Pick 3
Pick 4
Pick 5
Pick 6
Pick 7
Pick 8
Pick 9
Pick 10
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
2
0.430415
0.449803
0.291539
0.337352
0
0
0
0
3
0.522267
0.169384
0.25584
0.272896
0.189623
0.23904
0.280125
0
4
0.328592
0.210636
0.104716
0.251524
0.411584
0.240777
0.161812
5
0.193881
0.177262
0.330738
0.119734
0.142067
0.238306
6
0.062917
0.174873
0.136601
0.089644
0.195193
7
0.009832
0.044003
0.157017
0.303903
8
0.005617
0.041472
0.055423
9
0.000448
0.003468
10
0.000022
Total
0.952682
0.947779
0.951896
0.955144
0.956589
0.956579
0.951549
0.958129
Strategy
As you can see in the table above, the greatest return is for the pick-10 at 95.81%.