WHAT ARE MY CHANCES? WHAT ARE THE PROBABILITIES?

Remember the formula for calculating probability:

Probability = Total number of favourable outcomesTotal number of equally possible outcomes

Calculate your probabilities in a card draw:

1. What is the possibility of drawing a Queen from a deck of cards?(Hint: there are 4 different suits in a deck of cards - hearts, diamonds,spades and clubs. Each suit has 13 cards, ranging from Ace or one to 10and then a Jack, Queen and King. Therefore, there are 13 cards in each of the 4 suits.) So, divide the total number of Queen cards (Answer: 4) by the total number of cards in the deck (Answer: 52) Answer: 4/52 or 1/13 (although not asked to calculate this, thepercentage is 7.7%).If you have a deck of cards, draw one and note which card it was:

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Was it a Queen? Yes / No

2. What is the possibility of drawing a number lower than 9 from a deck ofcards?(Hint: there are 4 suits with numbers 1-10, Jack, Queen and King in each.In this case, an Ace counts as 1) (Answer: each suit has 8 cards lower than9, i.e. numbers 8,7,6,5,4,3,2,and Ace. There are 4 suits, therefore thetotal number of cards less than 9 are 8x4 = 32. Divide by the total numberof cards = 52. Answer: 32/52 or 8/13 (although not asked to calculate this, thepercentage is 61.5%)If you have a deck of cards, draw one and note which card it was:

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Was it a lower than 9? Yes / No

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Calculate the probabilities in a Lotto draw:

3. In a Lotto game you choose 6 numbers from 1-49. The total number ofcombinations of winning the 1st prize (of getting all 6 numbers) is :49 x49 x 49 x 49 x 49 x 49 (or 496). The probability of winning first prize is1 in 14 million! Therefore, there a good chance you could win 1st prize. True or false? (Answer: False!)

4. In a Lotto draw, you stand a better chance (i.e. a higher probability) ofwinning if you:a) chose numbers that have not been in the previous week's winning

numbers. (Answer: False)b) just choosing the numbers 1,2,3,4,5,6 every time? True or false? (Answer: False. The process of selecting the numbers in a Lotto draw istotally random. That means there is no pattern, no connection between thenumbers chosen or between the previous weeks' draws and the currentone. Each of the 49 numbers has an equal chance of being drawn for eachof the 6 slots. You therefore stand the same chance of winning if you chose1,2,3,4,5,6 every week or 13,1,8,27,33,46 every week, or somecombination based on birthdays, or any other combination of sixnumbers.)

Calculate the probability in everyday occurrences:

5. Eighteen athletes with numbers 1 to 18 are running in the school race. Theprobability that the athlete numbered 7 will win is 1/18. True or false? (Answer: False. Running a race is not a random event. It is determinedlargely by skill and training. Of course, luck, as in all matters of life, canalso play a part, for example if the fastest runner happens to be sufferingfrom a bad cold that day.)

6. A couple has 3 daughters. If they have another baby it is likely to be a boybecause 4-girl families are uncommon. True or false?

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Answer: False. It is true that 4-girl families are uncommon, but in general having had a boy or girl previously has no influence on the genderof the next child, i.e., we assume that births are independent events.Actually, this isn't entirely accurate. The true probability is not exactly50/50 due to rates of conception, miscarriages, and other environmentaland physiological factors. A boy is more likely to be born (with aprobability of 51.21%) than a girl (with a probability of 48.79%).

7. There are 26 letters in the English alphabet. If I select a letter at randomfrom the page of an English novel, the probability that it will be an “e” is1/26. True or false?Answer: False. As any Scrabble player knows, there are some letters (likevowels) that appear much more often than other letters (like x or y).

8. Elizabeth doesn't know the answer to a 4-answer multiple choice question.She is going to guess a, b, c or d. The probability that she will guessincorrectly is 3/4. True or false?Answer: True.

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