Idea of Probability
James flips a coin 3 times and gets: heads, heads, heads. What is the probability that he gets heads on his next coin flip?
0.5
You flip two coins. What is the probability that you get heads and then heads again?
0.25
What percent of students only love art?
0.1
P(Play Baseball)
0.36
P(don’t play a sport)
0.58
Below is the data on students' favorite subject. What is the probability that someone’s favorite subject is History?
Math Science History English Foreign Lang/Elective
0.2 0.1 ? 0.15 0.3
0.25
A bag contains 6 blue marbles, 2 red marbles and 3 green marbles. You draw 3 marbles WITH REPLACEMENT. What is the probability that you get 3 blue marbles?
0.162
P (Love Math AND Love Art)
0.65
P(Don’t Play Football)
0.69
P(plays a sport OR takes an AP class)
=0.49
The law of large numbers says that the mean outcome in many repetitions eventually gets close to:
a) The middle value or category
b) The expected value
c) The outcome with the largest probability
d) The outcome with the smallest probability
e) No single particular value
b) The Expected Value
A bag contains 6 blue marbles, 2 red marbles and 3 green marbles. You draw 3 marbles WITHOUT REPLACEMENT. What is the probability that you get 3 blue marbles?
0.121
P(Love Math OR Love Art)
0.93
P(Female OR Basketball)
.52 +.31 -.16 = 0.67
P(doesn’t play a sport AND doesn’t take an AP class)
0.51
Mutually exclusive means to events cannot _____________________________________.
Happen at the same time
A woman has three kids and all of them are boys. What is the probability of this happening?
0.125
P (Does Not Love Math)
0.17
P(Play Football AND are Male)
P(plays a sport | takes an AP class)
0.8
P(A^c) = 1- _______
P(A)
A person is a 70% free throw shooter. They shoot 3 shots. What is the probability that the make, make and then miss?
0.147
P(Does Not Love Math And Does Not Love Math)
.07
P(Plays Basketball | Female)
.16 /.52 = .31 OR 16/52=0.31
P(takes an AP class | plays a sport)
0.67