Keno

## Description

_Keno_ is a simulation of the casino game bearing the same title. There are
several variations of Keno, but in this case the player chooses a maximum of
10 numbers between 1 and 80. The game randomly draws 20 numbers by throwing
balls on the board. If the balls land on the player’s choices, he is rewarded
with tokens. When it was first released, tickets to prize drawings were
offered instead of tokens. The amount of tokens won depends on how many
numbers were correctly guessed and on the ratio between them and the total
number of choices. For example, the rewards are bigger if you correctly guess
three numbers out of three choices, compared to three out of ten choices.