Probability Opposite Events

In probability theory, the sum of an event (A) occurring and the same event NOT occurring (not A) is always - 

• 0

• based on the sample space

• variable

• 1

Which of the following expressions would be used to calculate the complement of an event occurring?

• P(event) - 1

• P(event 1) x    P(event 2)

• P(event)/possible outcomes

• 1 - P(event)

P(A) + P(not A) = 1

• True

• False

The likelihood that an event will NOT occur is known as its - 

• complement

• sample space

• opposite

• trial

Event A has a probability of 0.3. What is the probability of the complement of Event A?

• 30%

• 3/100

• 7/100

• 0.7

P(not A) = 
*Remember to simplify.*

• 6/8

• 3/4

• 2/8

• 1/4

​ (a)   are two events that together contain all of the outcomes in the sample space.

• equally likely

• simple event

• Experiment

• outcome

• Complementary Events

• probability

If 33% of the students at Harnett Central have a pet, then what is the probability of the complement of this event?

• 33%

• 77%

• 67%

• 50%

Six of the 6 numbers are greater than 0. Spinning a number that is greater than 0 is...

• impossible

• unlikely

• as likely as not

• likely

• certain

Find P (not A)

Mathematical Equivalence

ON