In a class of 25 students, 5 were tardy. What is the probability that a randomly selected student was tardy?
.2
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 6
6/10 = .6
Assuming 20 students were surveyed, how many did neither swimming or athletics
8
You have four different pants, three different shirts, and three different pairs of shoes. How many combinations of pants, shirts, and shoes can you wear?
4 x 3 x 3
= 36
What is the probability that a randomly selected person will be right handed?
.87
Two events that cannot happen simultaneously are...
Mutually Exclusive
You roll a six sided die once. What is the probability of getting an odd number?
.5
How many students are taking only history?
13
Compute P(7,6)
5040
What is the probability that a randomly selected person will be left handed given that they are female
1/12
A bowl contains four apples, three bananas, three oranges, and two pears. If two pieces of fruit are selected at random, what is the probability of selecting an orange and a banana?
3/22
At a local high school, 34% of the students take a bus to school and 56% of the students walk to school. Find the probability of randomly selecting a student that takes a bus or walks to school and determine if these events are mutually inclusive or exclusive?
*assume their is only one way to get to school
90%
These events are mutually exclusive. You cannot walk and take the bus to school, hence there is no intersection between them
How many students are taking History (H) or Geography (G)
27
A company needs to choose an 8 person board of directors. If 24 different people applied, how many possible groups can there be?
C (24, 8) = 735,471
What is the probability that a randomly selected person will be male given they are right handed
43/87
The probability of randomly selecting two dimes from a bag containing 10 dimes and 8 pennies if the first selection is replaced
25/81
There are 3 red marbles, 2 green marbles. One marble is taken out and not replaced. A second marble is then taken out. What is the probability that a red marble and then another red marble is chosen
3/10
How many students play only soccer or only hockey
23
Five different books are on a shelf. In how many different ways could you arrange them?
5x4x3x2x1
120
You may also see that P (5,5) works here
What is the probability that a randomly selected person will be young or sold given that they are male
20/38
What is the probability of rolling two dice and getting a sum greater than 10
1/12
A survey of the junior class at SPF high school shows that 2/5 of the students who have home computers use them for word processing, 1/3 use them for playing games, and 1/4 use them for both word processing and playing games. What is the probability that a student with a home computer uses it for word processing or playing games?
P(AorB)= P(A) + P(B) - P(AandB)
P(AorB)= 2/5 + 1/3 - 1/4
= 24/60 + 20/60 - 15/60
29/60
How many students play Netball or Soccer
77
Compute:
120! / 118!
14,280
It's just 120 x 119
Everything else cancels out
What is the probability that both the age and gender of a randomly selected person is "missing"
25/1025