Originally Posted by Hatake Kakashi
no its not 21/40 because you are only drawing 7 cards not 21 and there are only 3 narutos. your thinking about it wrong trust me
If three cards in your deck are Naruto cards, and you draw one card with a full deck, there is a probability of 3/40 that the card you drew is a Naruto card. If your first hand is made up of seven cards, starting with a full deck, each of those cards has a 3/40 chance of being a Naruto card. With seven cards, that's a three times seven out of 40, or 21/40, or 52.5% chance of one of them being a Naruto card. Of course, this math is a bit rough, since you have one less card in your deck each time you draw a card in that first hand of seven cards, but that only increases your theoretical chances of drawing at least one Naruto card in your first hand. Calculating the chances of more than one of them being a Naruto card or calculating what would happen if you redraw your hand is a bit more difficult, though. If you want to test it, go make a deck of 40 cards of anything with three of a certain card in it, shuffle the deck well, and draw seven cards. You will theoretically have about a 50-50 chance of getting at least one of those three cards with that first draw.