Calculate the probability of completing when you draw a gacha and the expected value to complete.

When you draw a specified number of times Gacha, the probability of completion is calculated.

Enter the type of card and the Gacha, the number of times that draw a card, and then click the button "calculate the probability", and calculated the expected value of the number of attempts to complete the Gacha there and if the probability of complete minus the specified number of times, and the specified type.