Batch 2 - Class 15 - Probability (1)

• Figure out your chances of winning a lucky seven game
• Take 13 cards of a suite (Ace, 2, 3, 4, ... , King). The game is as follows: you pick two cards, and then the third. If the third card is between the first two cards, you win. What are the chances of your winning?

  If you solve the 13 card puzzle, try the same with all 52 cards

• Probability of a dice roll resulting in number 3 (Answer: 1/6)

  Why? Kids are likely to come up with "one face out of 6"Verify by rolling the dice 30 times - emphasize that probability problems are essentially counting problemsGet kids to take examples where one can do probability as in above case
• Coin tosses - Chances of heads, Chances of one head and one tail in two throws, Chances of first head and second tail in two throws
• We can randomly color each face of a dice yellow or blue. What are the chances that exactly one face is blue? (Answer: 6/2^6 = 3/32)
• Game of Russian Roulette - Do you want to go first or second? (Answer: Doesn't matter)
• MartinShCol - 2.1 - If 52 cards are dealt to 4 people, what is more likely - that me and my partner have all clubs, or no clubs (Answer: they are the same)
• MartinShCol - 2.2 - If you stuff four letters randomly into 4 envelopes, what is the probability of exactly three being in right envelopes (Answer: zero)
• Shakuntala - 142 - a man has 2 kids, at least one is a girl. What is prob of both being girls (Answer: 1/3)
• Construct a probability experiment that gives 4/5 result (Answer: For example, take 5 cards, and prob of not picking the lowest one in a random shuffle)
• FirstMensa - 118 - A roulette has 1-36 numbers. A man bets no 20 10 times, and loses all 10 times. On the next turn, should he bet 10 or 20? What are the odds (Answer: Any, 1/36)