Playing with Probability
Probability expresses the likelihood or odds of something to happen. If the weather forecasts 20% chances of rain odds are that it will not rain. Another example of probability are raffles. You put your name on a ticket along with 9 other people with tickets. What are the odds that your ticket will be chosen? Since there are 10 tickets the likelihood of your ticket being drawn is 1 in 10. This means if a ticket is drawn 10 times your ticket will be drawn once. However, probability is based on statistics and the odds can work in your favor. All 10 people who had their name on a ticket all have the same 1 in 10 chance of being chosen. The winner whose ticket is drawn beat the odds. Therefore, probability is theoretical. Another good way to conceptualize probability is with a standard deck of playing cards.
How does probability compare with the actual outcome?
- Standard deck of playing cards
- Using a standard deck of cards (without the Jokers) pick a card.
- Place the card back in the deck and shuffle the cards.
- What is the probability of choosing that same card?
- Pick another card. Was it the same or a different card? How did the probability compare with the actual outcome?
- Shuffle the cards.
- What is the probability of choosing a red card? How did the probability compare with the actual outcome?
- Gather only the face cards (king, queen, & jack) and shuffle.
- What is the probability of drawing a queen?
- From the stack of face cards draw a card the same number of times as the denominator. For example: If the probability of drawing a jack is 1/5, draw 5 cards. Did you draw a jack within those 5 draws?
- Record which card you draw. How did the actual outcome compare with the probability?
- Think of other examples and compare the probabilities with the outcomes.
- How does probability factor in when performing card tricks
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.