List of top Quantitative Aptitude Questions on Probability

In a certain show, a lottery ticket is numbered consecutively from 100 through 999 (both inclusive). What is the probability that a randomly selected ticket will have a number with a ten’s digit as “3”?
In a certain medical survey, 45 percent of the people surveyed had the type A antigen in their blood and 3 percent had both the type A antigen and the type B antigen. Which of the following is closest to the percent of those with the type A antigen who also had the type B antigen? [Official GMAT-2018]
A certain club has 10 members, including Harry. One of the 10 members is to be chosen at random to be the president, one of the remaining 9 members is to be chosen at random to be the secretary, and one of the remaining 8 members is to be chosen at random to be the treasurer. What is the probability that Harry will be either the member chosen to be the secretary or the member chosen to be the treasurer?
In a group of 80 students, 24 are enrolled in geometry, 40 in biology, and 20 in both. If a student were randomly selected from the 80 students, what is the probability that the student selected would not be enrolled in either course?
A certain jar contains 100 jelly beans: 50 white, 30 green, 10 yellow, 5 red, 4 purple, and 1 black. If a jelly bean is to be chosen at random, what is the probability that the jelly bean will be neither purple nor red?
An experiment has three possible outcomes, I, J, and K. The probabilities of the outcomes are 0.25, 0.35, and 0.40, respectively. If the experiment is to be performed twice and the successive outcomes are independent, what is the probability that K will not be an outcome either time?

A marble is to be drawn at random from a bag that contains 2 yellow marbles, 4 blue marbles, 6 green marbles, and no other marbles.
 

Column AColumn B
The probability that the marble drawn will be greenThe probability that the marble drawn will be yellow or blue


 

Two beads are to be independently and randomly selected, one from each of two bags. If \(\frac{2}{7}\) of the beads in one bag and \(\frac{3}{7}\) of the beads in the other bag are yellow, what is the probability that both beads selected will be yellow?
Integer n will be randomly selected from the integers 1 to 13, inclusive.
Column A: The probability that n will be even
Column B: The probability that n will be odd
The odds in favor of winning a game can be found by computing the ratio of the probability of winning to the probability of not winning. If the probability that Pat will win a game is \(\frac{4}{9}\), what are the odds that Pat will win the game?
One integer will be randomly selected from the integers 11 to 60, inclusive. What is the probability that the selected integer will be a perfect square or a perfect cube?
A box contains 20 marbles, all of which are solid colored; 5 of the marbles are green and 10 of the marbles are red.
Column A: The probability that a marble selected at random from the box will be green
Column B: The probability that a marble selected at random from the box will be neither red nor green
The probability that events E and F will both occur is 0.42. The probability that event E will occur is 0.58.
Column A: The probability that event F will occur
Column B: 0.58
The probabilities that each of two independent experiments will have a successful outcome are \(\frac{8}{15}\) and \(\frac{2}{3}\), respectively. What is the probability that both experiments will have successful outcomes?
Master Chef Alan makes a dish every day from one of his recipe books. He has written 3 books and each book contains 15 different recipes. What is the probability that he will cook 4th dish from 3rd book today?
At a medical research lab, nine doctors are conducting multiple clinical trials. Six of the doctors are working on a clinical trial with exactly one other doctor and three doctors are working on a clinical trial with exactly two other doctors. If two doctors are selected at random from the lab, what is the probability that those two doctors are NOT working together on a clinical trial?