Warm-up
■ Solve the System:
Solve and Graph the solution:
■ 2x + 3y = 5
■ -7x + 6y = -1
3 ≤ 2𝑥 − 5 < 7
PROBABILITY PART
TROIS
11.5
And
Means
Multiply
Consider whether or not the first event
effects the second event
When selecting objects, WITH REPLACEMENT, means the
object was replaced before choosing the next object.
WITHOUT REPLACEMENT, means that you continue to select
objects without returning them.
Examples
■ You roll two dice, what is the probability of rolling a 2 on
the first and a multiple of 3 on the second?
■ You have 5 dimes and 4 nickels in your pocket. You
reach into your pocket and pull out one coin, put it back,
and then pull out another coin. What is the probability
that you pulled a nickel and then a dime?
■ What is the probability of pulling a dime, not replacing it,
then pulling another dime?
Examples
■ A teacher needs to send 2 students to a conference.
He randomly selects two students from a group of 2
freshman, 3 sophmores, 5 juniors, and 3 seniors.
What is the probability that a junior and then a
senior is taken?
■ What is the probability that two freshman are taken?
Homework