Observations and results
Did it take fewer draws to reach a certain color than it took to reach a certain suit or kind of card? Did it take even more draws to reach a specific card?
Mathematicians measure probability by counting and using some very basic math, like addition and division. For example, you can add up the number of spades in a complete deck (13) and divide this by the total number of cards in the deck (52) to get the probability of randomly drawing a spade: 13 in 52, or 25 percent. If you were investigating red cards, kings or the queen of hearts, the odds of randomly drawing one of these from a complete deck are 50 percent (26 in 52); about 7.7 percent (four in 52); or about 1.9 percent (one in 52), respectively. This is why, on average (when done over enough trials), it is easier to draw a red card than a spade, a spade than a king, and a king than the queen of hearts. As you draw cards from a deck, the odds of finding your card change. For example, if you are looking for a spade and do not get it on your first draw, there are still 13 spades in the deck but the deck now holds only 51 cards, so your odds of drawing a spade on the second draw are 13 in 51, or about 25.5 percent. This may not seem like much of an improvement, but with every draw the odds continue to increase.
More to explore
Unraveling Probability Paradoxes from Scientific American
Calculating the Probability of Simple Events from neoK12
4 Great Math Games from Scholastic, Inc.
Classified Index of Card Games from John McLeod
Pick a Card, Any Card from Science Buddies
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