1. LO:
Show that some events are more likely
to occur than others
Express the likelihood of an event using fraction,
decimals and percentages with the probability scale

2. Talking about probability

3. Is it possible to win a million or more on the Lotto?
Discuss: how you would describe likelihood of winning the Lotto?

4. How do we measure probability?

5. PROBABILITY SCALE

6. Where do you think ‘Winning the Lotto’ goes ?
the Sun will rise tomorrow
a baby will be a girl
certain
impossible

7. 1 2 EATING JUNK FOOD AND AVOIDING EXERCISE WILL MAKE YOU LOSE WEIGHT
IMPOSSIBLE
UNLIKELY
EVEN
LIKELY
CERTAIN
EATING JUNK FOOD
AND AVOIDING EXERCISE
WILL MAKE YOU LOSE WEIGHT 1
EATING 5 FRUIT AND VEGETABLES PER
DAY HELPS PREVENT DISEASE 2

8. 3 GOOD ATTENDANCE AT SCHOOL HAS A POSITIVE EFFECT ON ACHIEVEMENT.
IMPOSSIBLE
UNLIKELY
EVEN
LIKELY
CERTAIN
GOOD ATTENDANCE AT SCHOOL HAS A
POSITIVE EFFECT ON ACHIEVEMENT. 3
THE NEXT BABY TO BE BORN IN SOUTHEND
IS GOING TO BE A BOY.

9. 5 NOVEMBER 29 FALLS ON A SUNDAY IN 2016
IMPOSSIBLE
UNLIKELY
EVEN
LIKELY
CERTAIN 5
NOVEMBER 29 FALLS ON A SUNDAY IN 2016
I WILL BE ABLE TO SPEAK FLUENT RUSSIAN
IN THE NEXT 5 MINUTES

11. How many Smarties are there altogether?20

12. All the Smarties are put back in the tube.
If I pick a Smartie at random, what is the probability that it is green?
Total number of Smarties = 20
Number of green Smarties = 1
Probability of picking green = 1 20

13. All the Smarties are in the tube.
If I pick a Smartie at random, what is the probability that it is brown?
Total number of Smarties = 20
Number of brown Smarties = 4
Probability of picking brown = 4 20 1 5 =

14. All the Smarties are in the tube.
If I pick a Smartie at random, what is the probability that it is orange or yellow?
Total number of Smarties = 20
Number of orange
and yellow Smarties = 7
Probability of picking
orange or yellow = 7 20

15. All the Smarties are in the tube.
If I pick a Smartie at random, what is the probability that it is not blue?
Number of not blue
Smarties = 17
Total number of Smarties = 20
Probability of not
picking blue = 17 20

16. What is the probability he picks a year 11 student?
Mr Brown puts all the pupils names in a hat and picks one at random.
What is the probability he picks a year 11 student?

17. Probability of an event
1. Bob is picking randomly from a bag containing tiles numbered 1 to 10.
Write down the probability that the number he picks is:
a) b) 4 or less c) Odd d) A multiple of 3

18. Probability of an event
2. A survey is conducted of pupils’ favourite team:
Team
Spurs
Man Utd
Liverpool
Arsenal
Pupils 12 8 4 6
John picks a pupil at random to ask more questions.
Write down the probability that the pupil he picks supports:
a) Liverpool b) A London team c) Not Liverpool

19. Probability of an event
3. A bag contains 20 coloured balls, some red and some blue.
Keith knows that the probability of picking a red ball is 2/5.
How many red balls are there?
8 red balls

20. Summer fayre probability worksheets