Statistics Conditional Probability

Given P(A) = .8 and P( B| A) = .3, find P( A and B).

• 2.6

• .12

• .24

• .38

If A and B are mutually exclusive, which statement below must be true?

• P(A∩B) = 0

• P(A|B) = 0

• P(A∪B) = 0

• P(A) + P(B) = 1

If A and B are independent, which statement must be true?

• P(A∩B) = 0

• P(A|B) = P(A)

• P(A∪B) = 0

• P(A) + P(B) = 1

When picking two cards from a pack (without putting the first one back) the two outcomes are:

• Dependent

• Independent

A science teacher gave her class two tests. 25% of the class passed both tests and 42% of the class passed the first test. What percent of those who passed the first test also passed the second?

• 59.5%

• 10.5%

• 1.6%

• Not enough information

What is P(Red given blue)?

• 50%

• 26.7%

• 57.1%

• 46.7%

What is P(T given C)?

• 45%

• 29.6%

• 40%

• 33.3%

P(Sandals|Pants):

• 4/20

• 6/15

• 1/2

• 2/7

P(Pizza|Senior):

• 10/15

• 4/5

• 2/3

• 10/5

What is the probability that a student does not play on a sports team? 

• .5

• .45

• .55