Simple Probability
What is the probability of choosing a month that starts with the letter J?
1/4
A city has 9 coffee shops: 3 Starbucks, 2 Caribou Coffees, and 4 Crazy Mocha Coffees. If a person selects one shop at random to buy a cup of coffee, Find the probability that it is either a Starbucks or Crazy Mocha Coffees.
7/9
A single card is drawn at random from an ordinary deck of cards. Find the probability that it is either an ace or a black card.
28/52 = 7/13
A coin is flipped and a die is rolled. Find the probability of getting a head on the coin and a 4 on the die.
1/12
In a standard deck of 52 cards, what is the probability of drawing one ace after another ace on two draws (no replacing)?
12/2652 = 1/221
The following M&M colors are in the bowl: 4 yellow, 6 orange, 3 green, 5 blue, 2 brown. What is the probability of selecting a brown candy?
2/20 = 1/10
A day of the week is selected at random. What is the probability of choosing a Monday or Tuesday?
2/7
In a hospital unit, there are 8 nurses and 5 physicians; 7 nurses and 3 physicians are females. If a staff person is selected, find the probability that the subject is a nurse or a male?
10/13
An bag contains 3 red marbles, 2 blue marbles, and 5 white marbles. A marble is selected and its color noted. Then it is replaced. A second marble is selected and its color noted. Find the probability of selecting 2 blue marbles.
4/100 = 1/25
A basket contains 5 purple pencils and 9 brown pencils. If two pencils are picked at random one after the other without replacement, then what is the probability that both the pencils are purple?
20/182 = 10/91
Find the probability of rolling greater than a 1 on a single die.
5/6
A number from 1 to 10 is chosen at random. What is the probability of choosing a 5 or an even number?
6/10 = 3/5
On New Year’s Eve, the probability of a person driving while intoxicated is 0.32, the probability of a person having a driving accident is 0.09, and the probability of a person having a driving accident while intoxicated is 0.06. What is the probability of a person driving while intoxicated or having a driving accident?
0.35
Approximately 9% of men have a type of color blindness that prevents them from distinguishing between red and green. If 3 men are selected at random, find the probability that all of them will have this type of red-green color blindness.
0.000729 or 0.0729%
There are 3 red, 1 blue, and 2 yellow marbles in a bag. Once a marble is selected, it is not replaced. Find P(red and then yellow).
6/30 = 1/5
In a 12-number spinner, there are 3 blue, 5 red, 1 yellow and 3 green. What is the probability of spinning green?
3/12 = 1/4
In a pet store, there are 6 puppies, 4 gerbils and 7 parakeets. If a pet is chosen at random, what is the probability of choosing a puppy or a parakeet?
13/17
The probability of a New York teenager owning a skateboard is 0.37, of owning a bicycle is 0.81 and of owning both is 0.36. If a New York teenager is chosen at random, what is the probability that the teenager owns a skateboard or a bicycle?
0.82
There are 7 green marbles and 3 yellow marbles in a bag. The marbles are identical except for their color. A marble is drawn at random in a bag, and is replaced. A second marble is then drawn at random from a bag. Find the probability that the first marble drawn is green and the second marble drawn is yellow.
21/100
Out of 33 students in a class, 21 study Geography and 12 study History. No student studies both subjects. Two students are picked at random from the class. Find the probability that the first student studies History and the second studies Geography.
252/1056 = 21/88
A 6-section spinner is numbered 1-6. What is the probability of spinning less than 4?
3/6 = 1/2
The letters of the word "MUTUALLY" and the word "EXCLUSIVE" are put into a box. A card is picked at random. What is the probability of picking a “U“ or a consonant? (Consider 'Y' a consonant in this case.)
13/17
A single 6-sided die is rolled. What is the probability of rolling a number greater than 3 or an even number?
4/6 = 2/3
What is the probability that both of your parents were born on a weekend? (Assume that each day is equally likely and that a weekend day is either Saturday or Sunday.)
4/49
Three cards are drawn from an ordinary deck and not replaced. Find the probability of getting 3 jacks.
1/5525