Dependent or Independent
You pick a card out from a standard deck and then flip a coin.
A) Are the following events independent or dependent?
B) What is the probability of picking a red card and getting a heads?
A) Independent
B) 26/52 * 1/2 = 1/4
At a local high school, 34% of the students take a bus to school and 56% of the students walk to school. What is the probability of randomly selecting a student that takes a bus or walks to school?
A) Are these events mutually exclusive or inclusive?
B) Determine the probability of the event
A) Mutually exclusive
B) 34/100 + 56/100 = 90/100
A bowl contains four apples, three bananas, three oranges, and two pears. If a fruit is selected at random, what is the probability of selecting an orange?
3/12
30 students are asked if they have a sister or a brother. 10 students have both a sister and a brother, 8 students only have a brother, 3 have neither.
How many only have a sister?
9 students
the set of all possible outcomes of an event.
sample space
How many cards in a standard deck of 52 cards are red?
26
Marianna has a box of 6 red and 2 green marbles, she selects a marble doesn't replace and selects another.
A) Are these events dependent or independent?
B) Determine the probability of selecting a red marble then a green marble.
A) Dependent
B) 6/8 * 2/7 = 3/14
A card is drawn from a standard deck of cards. What is the probability of drawing a Jack or a Heart?
A) Are these events mutually exclusive or inclusive?
B) Determine the probability of the event
A) Mutually inclusive
B) 4/52 + 13/52 - 1/52 = 4/13
What is the probability of selecting a yellow or blue marble from a box of 5 green, 3 yellow, and 2 blue marbles?
P(yellow or blue)= P(yellow) + P(blue) = 1/2
40 students were asked about their music preferences. 20 students like hip-hop, 6 students like both hip-hop and rock, and 18 like rock.
How many students like hip-hop or rock?
32 students
The ratio of the number of favorable outcomes to the total number of outcomes.
Theoretical Probability
Find the number of possible outcomes in the sample space when you flip a coin and draw a marble from a bag containing two purple marbles and one white marble.
6
You flip a coin three times in a row.
A) Are these events independent or dependent?
B) Find the probability of getting two heads
A) Independent
B) 1/2 * 1/2 * 1/2= 1/8
On a school board, 2 of the 4 female members are over 40 years of age, and 5 of the 6 male members are over 40. If one person did not attend the meeting, what is the probability that the person was a male or a member over 40?
A) Are these events mutually exclusive or inclusive?
B) Determine the probability of the event
A) Mutually inclusive
B) P(male or over 40)= 6/10+ 7/10 - 5/10= 8/10 = 4/5
What is the probability of rolling two dice and getting a sum greater than 10
(5,6), (6,5), or (6,6)
3/36= 1/12
The sum of the probability of an event and the probability of the complement of the event is always
equal to 1 (one)
How many faces on a six-sided die are factors of 6? List them.
4
one, two, three, and six
Jack had 4 Snicker bars and 8 Mars bars. He randomly chose a piece of candy, ate it, then chose another.
A) Are these events Dependent or Independent?
B) What is the probability that both candy bars were snickers?
A) Dependent
B) 4/12 * 3/11= 1/11
What is the probability of selecting a card from a standard deck of cards and the card is a 10 or an ace?
A) Are these events mutually exclusive or inclusive?
B) Determine the probability of the event
A) Mutually exclusive
B) 4/52 + 4/52= 8/52 = 2/13
A bag contains 3 black, 5 green, and 4 yellow marbles.
What is the probability that a marble selected at random will be black?
3/12
In a survey of 120 people, 65 said they could ride a bike, 50 could swim, and 40 could do neither. How many people can ride a bike and swim?
35 people
Events that can not happen at the same time are
mutually exclusive
Find the number of possible outcomes in the sample space when you roll a die and flip two coins.
24
There are two traffic lights along the route that Ms. Prybella drives from home to work. One traffic light is red 50% of the time. The next traffic light is red 60% of the time. The lights operate on separate timers. Find the probability that these lights will both be red on Ms. Prybella's way home from work.
A) Are these events independent or dependent?
B) Determine the probability that both lights will be red
A) Independent
B) 50/100 * 60/100 = 3/10
On a spinner labeled with numbers 1-10, where each number is equally likely to be spun, determine the probability of spinning an odd number or a multiple of 3.
A) Are these events mutually exclusive or inclusive?
B) Determine the probability of the event
A) Mutually inclusive
B) 5/10 + 3/10 - 2/10 = 6/10 = 3/5
Find the probability of randomly selecting 3 red pencils from a box containing 5 red, 3 blue, and 4 green pencils
1/22
There are C(5,3) ways to select 3 out of 5 red pencils and C(12,3) ways to select 3 out of 12 pencils
The ratio of the number of favorable outcomes to the number of trials in an experiment.
Experimental Probability
How many cards in a deck are black or a jack?
28