Two Way Tables
Basic Probability
Independence
General Probability Rules
100
How many students participated in the survey?
160
100
If you flip a fair coin once, what is the probability of getting a heads?
1/2=50%
100
If you flip a fair coin three times, what is the probability of getting tails each time?
1/2*1/2*1/2=1/8=12.5%
100
Suppose events A and B are independent. How would we calculate the probability of A AND B occurring?
P(A and B)=P(A)*P(B)
200
What is the probability that a student like skateboards and snowmobiles?
80/60=1/2=50%
200
If a bag has 3 red balls, and 5 green balls, what is the probability of randomly picking one red ball out of the bag?
3/8
200
1/5*1/6=1/30=3.3%
200
Consider an event A. How would we calculate the probability of the COMPLIMENT of A?
1-P(A)
300
What is the probability that student does not like skateboards and does not like snowmobiles?
10/160=1/16=6.25%
300
if you flip a fair coin once, what is the probability of getting a heads OR tails after one toss?
1=100%
300
What is the probability that Tylee misses one and makes two free throws?
(.3)(.7)(.7)=14.7%
300
Suppose events A and B are non-mutually exclusive. How would we calculate the probability of A or B happening?
P(A)+P(B)-P(A and B)
400
what is the probability of a student having blue eyes IF they were not wearing yellow?
2/22=1/11=9%
400
A six sided die is tossed twice, what is the probability of getting an even number on each toss?
3/6*3/6=1/2*1/2=1/4
400
(.8)(.8)=64%
400
How would you calculate the probability of an event occurring at least once?
P(at least 1)=?
1-P(none)
500
What is the probability of a student having blues eyes OR wearing yellow?
(12+40-10)/62=42/62=21/31=67.7%
500
A standard deck of cards has 52 cards (excluding jokers) in total. If you pick one card at random out of the deck, what is the probability of getting a face card?
Hint: face cards = jack, queen, king
12/52=3/13=23.1%
500
(4/52)(13/52)(4/52)=(1/13)(1/4)(1/13)=1/676=.15%
500
Suppose we have a z-score of 1 and a z-score of -1. How would we calculate the probability (the area under the curve) between these two z-scores?
Bonus points: Tell me the probability or percentage
P(Z<1)-P(Z<-1)=68%