Four coins are thrown simultaneously. What is the probability of getting at least one head ?
A bag contains 4 red and 3 black balls. A second bag contains 2 red and 4 black balls.
One bag is selected at random. From the selected bag , one ball is drawn
Find the probability that the ball drawn is red
A problem is given to three students whose chances of solving it are 1/2 , 1/3 and 1/4 respectively
Find the probability that the problem is solved by at least one of them
The turn out of spectators at a motor rally is dependent upon the weather.
On a rainy day the probability of a big turn out is 0.4, but if it does not rain , the probability of a big turn out increases to 0.9
The weather forecast gives the probability of 0.75 that it will rain on the day of the race
Find the probability that there is a big turn out
Let A and B be two events such that P (A) = 0.3 , P( B) = 0.4 and P (A U B) = 0.5
Then P ( B/A) = ......................
A bag A contains 2 white and 3 red balls and another bag B contains 4 white and 5 red balls.
One bag is chosen at random and a ball is is drawn from it at random.
The ball drawn is found to be red.
What is the probability that the ball is drawn is from Bag B ?
Three bulbs are selected at random from 20 bulbs of which 5 are defective.
What is the probability that exactly one of the three bulbs selected is defective ?
Let X be a random variable representing the Binomial distribution B ( 6 , 1/4 )
Then P ( X = 3 ) = .........................................
Let a pair of dice be thrown and the random variable X be the sum of the numbers that appear on the two dice.
The mean or expectation , E(X) of the probability distribution for the random variable X is ...........................
A veterinary doctor interviews 100 of her clients. She finds that :
25 own dogs 53 own cats 40 own tropical fish
15 own dogs annd cats 10 own cats and tropical fish 11 own tropical fish and dogs
7 own dogs, cats and tropical fish
Find the probability that a client does not own any of these three types of pets