PPT: Probability

 Page 1


PROBABILITY
Page 2


PROBABILITY
VOCABULARY
? Outcome – one possible result of a probability.
? Sample Space – the list of possible outcomes 
for a probability event.
? Random – outcomes that occur at random if each 
outcome is equally likely to occur.
? Simple Event – a specific outcome or type of 
outcome. 
? Complementary Events – the events of one 
outcome happening and that outcomes not 
happening are complimentary; the sum of the 
probabilities of complementary events is 1.
Page 3


PROBABILITY
VOCABULARY
? Outcome – one possible result of a probability.
? Sample Space – the list of possible outcomes 
for a probability event.
? Random – outcomes that occur at random if each 
outcome is equally likely to occur.
? Simple Event – a specific outcome or type of 
outcome. 
? Complementary Events – the events of one 
outcome happening and that outcomes not 
happening are complimentary; the sum of the 
probabilities of complementary events is 1.
REAL WORLD EXAMPLE:
Best Buy is having an IPOD giveaway. They put
all the IPOD Shuffles in a bag. Customers
may choose an IPOD without looking at the
color. Inside the bag are 4 orange, 5 blue, 6
green, and 5 pink IPODS. If Maria chooses
one IPOD at random, what is the probability
she will choose an orange IPOD?
P(orange) =
4
/
20
=
2
/
10
=
1
/
5
or 20%
Page 4


PROBABILITY
VOCABULARY
? Outcome – one possible result of a probability.
? Sample Space – the list of possible outcomes 
for a probability event.
? Random – outcomes that occur at random if each 
outcome is equally likely to occur.
? Simple Event – a specific outcome or type of 
outcome. 
? Complementary Events – the events of one 
outcome happening and that outcomes not 
happening are complimentary; the sum of the 
probabilities of complementary events is 1.
REAL WORLD EXAMPLE:
Best Buy is having an IPOD giveaway. They put
all the IPOD Shuffles in a bag. Customers
may choose an IPOD without looking at the
color. Inside the bag are 4 orange, 5 blue, 6
green, and 5 pink IPODS. If Maria chooses
one IPOD at random, what is the probability
she will choose an orange IPOD?
P(orange) =
4
/
20
=
2
/
10
=
1
/
5
or 20%
WHAT IS A PROBABILITY?
- Probability is the chance that some event will 
happen
- It is the ratio of the number of ways a certain 
event can occur to the number of possible 
outcomes
number of favorable outcomes
P(event) =
number of possible outcomes
Examples that use Probability:
(1) Dice, (2) Spinners, (3) Coins, (4) Deck of 
Cards, (5) Evens/Odds, (6) Alphabet, etc.
Page 5


PROBABILITY
VOCABULARY
? Outcome – one possible result of a probability.
? Sample Space – the list of possible outcomes 
for a probability event.
? Random – outcomes that occur at random if each 
outcome is equally likely to occur.
? Simple Event – a specific outcome or type of 
outcome. 
? Complementary Events – the events of one 
outcome happening and that outcomes not 
happening are complimentary; the sum of the 
probabilities of complementary events is 1.
REAL WORLD EXAMPLE:
Best Buy is having an IPOD giveaway. They put
all the IPOD Shuffles in a bag. Customers
may choose an IPOD without looking at the
color. Inside the bag are 4 orange, 5 blue, 6
green, and 5 pink IPODS. If Maria chooses
one IPOD at random, what is the probability
she will choose an orange IPOD?
P(orange) =
4
/
20
=
2
/
10
=
1
/
5
or 20%
WHAT IS A PROBABILITY?
- Probability is the chance that some event will 
happen
- It is the ratio of the number of ways a certain 
event can occur to the number of possible 
outcomes
number of favorable outcomes
P(event) =
number of possible outcomes
Examples that use Probability:
(1) Dice, (2) Spinners, (3) Coins, (4) Deck of 
Cards, (5) Evens/Odds, (6) Alphabet, etc.
What is a PROBABILITY?
0% 25% 50% 75%  100%
0 ¼ or .25   ½ 0r .5 ¾ or .75 1
Impossible Not Very     Equally Likely     Somewhat       
Certain
Likely Likely
0 ¼ or .25 ½ 0r .5 ¾ or .75 1
Impossible Not Very 
Likely 
Somewhat
Likely
Equally 
Likely
Certain