Scratch cards – is a well-known instant lottery tickets where it is necessary to erase a protective layer and to detect a few matching symbols to win. John Koza invented scratch cards in 1974 the turnover of the lottery of Massachusetts was increased by almost three times for the week thanks to their implementation!
Actually, the basic version of the scratch cards online is no different from real analogies. You can choose a bet value, take a lottery card, “erase” and learn about the winning. Some games emulate a coin, and you can erase by hovering the mouse pointer (scratch card means something like “a card to erase”). However, it is usually easier to click the button Show Card or Scratch All to immediately open contents of the card. In the classic version, you must collect three of the same symbol from the six to get a win. Often digits of the winning coefficient, for example, from 1 to 100 or some in-game characters, for which a separate pay table are offering, printed on the card.
Scratch cards are available in most casino with a popular software. There can be no strategy in games. It is also difficult to estimate the mathematical expectation without knowing the frequency of the different symbols occurrence, but I think that mostly it lies in the range of 85-95%.
A list of websites with this game: