1. Grade 8 | Unit 8.3 | Page 10
Unit 8.3
Learning Activity Sheet - page i
WHAT ARE MY CHANCES? WHAT ARE THE PROBABILITIES?
Write down the names of the members of the group: ____________________________________________________
_________________________________________________________________________________________________
Remember the formula for calculating probability:
Probability = Total number of favourable outcomes
Total number of equally possible outcomes
Calculate your probabilities in a card draw:
1. What is the probability of drawing any Queen from a deck of cards?
(We assume that the card is drawn from a full deck of cards, that no other cards have already been drawn or dealt.
That would change the probabilities!)
(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 10 and then a Jack, Queen and King. Therefore, there are 13 cards in each of the
4 suits.)
The probability is: __________________ (may be expressed as a fraction or a decimal)
(Hint: Divide the total number of Queen cards by the total number of cards in the deck)
If you have a deck of cards, draw one and note which card it is: ____________
Was it a Queen? Yes/ No
2. What is the possibility of drawing a number lower than 9 (i.e. 8, 7, 6, 5, 4, 3, 2, ace) from a deck of cards?
The probability is: ________________ (may be expressed as a fraction or a decimal)
(Hint: Divide the total number of cards that are lower than 9 - remember there are 4 suits of each! - by the total
number of cards in the entire deck)
If you have a deck of cards, draw one and note which card it is: ____________
Was it a lower than 9? Yes/ No

2. Grade 8 | Unit 8.3 | Page 11
Learning Activity Sheet - page ii
Calculate the probabilities in a Lotto draw:
3. In a Lotto game you choose 6 numbers from 1-49. The total number of combinations of winning the 1st prize (of
getting all 6 numbers) is : 49 x 49 x 49 x 49 x 49 x 49 (or 496
). The probability of winning first prize is
1 in 14 million! There is therefore a good chance you could win.
True or false?
4. In a Lotto draw, you stand a better chance (i.e. a higher probability) of winning if you:
a) chose numbers that have not been in the previous week's winning numbers
True or false?
b) just choosing the numbers 1,2,3,4,5,6 every time.
True or false?
Calculate the probability in everyday occurrences:
5. Eighteen athletes with numbers 1 to 18 are running in the school race. The probability that the athlete numbered
7 will win is 1/18.
True or false? Why?
6. A couple has 3 daughters. If they have another baby it is likely to be a boy because 4-girl families are uncommon.
True or false? Why?
7. There are 26 letters in the English alphabet. If I select a letter at random from the page of an English novel, the
probability that it will be an “e” is 1/26.
True or false? Why?
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 guess incorrectly is 3/4.
True or false? Why?