11.3-11.4 Review
Quiz Tomorrow
Formulas
AND
Independent:
P(A and B) = P(A) x P(B)
Dependent:
P(A and B) = P(A) x P(B given A)
OR
Exclusive:
P(A or B) = P(A) + P(B)
Inclusive:
P(A or B) = P(A) +P(B) – P(A and B)
Indpendent/dependent and
what’s the probability
Flipping a heads, flipping a tails, and then flipping a
tails
A magic hat has 4 rabbits, 2 scarves, and 6 ping pong
balls. What is the probability a magician pulls out a
rabbit and then a ping pong ball (without replacement)
Mutually exclusive / inclusive
What is the probability I roll a 4 or a 5?
What is the probability I roll a number greater than 3 or I
roll a 5?
Word Problem
Of 1000 students interviewed, 300 had exercised over
the weekend. 400 of the students who were
interviewed played video games over the weekend. 100
of the people who exercised also played video games.
What is the probability that someone from this
interview played video games or exercised over the
weekend.
Word Problem
4 friends head to the vending machine for a snack after
school. The vending machine has 14 options for
snacks. What is the probability that at least two friends
had the same snack?
What is the probability that a first serve went in given
that he lost?
What is the probability that roger got the first serve in
and won?