Bag A contains 9 red marbles and 3 green marbles. Bag B contains 9 black marbles and 6 orange marbles. Find the probability of selecting one green marble from bag A and one black marble from bag B.
A box contains 5 purple marbles, 3 green marbles and 2 orange marbles. Two marbles are selected. Draws are made without replacement. Find P(1st orange then green).
A bag contains 5 red marbles and 4 pink marbles. A marble is randomly drawn and then replaced. What is the probability the first marble is pink and the second is red?
Two fair dice are rolled. Determine the probability of obtaining exactly two sixes.
Two fair dice are rolled. Determine the probability of obtaining a sum greater than six.
A delegation of six students is to be selected from a group of 10 girls and 8 boys. Determine the probability that equal numbers of girls and boys are chosen.
A fair die is tossed. Calculator the probability of obtaining a prime number.
Three fair coins are tossed. Calculate the probability of obtaining exactly 2 heads.
A fair octagonal die, labelled A, B, C, D, E, F, G and H is rolled twice. Calculate the probability of obtaining a vowel and a consonant.
A box contains 5 red and 15 green balls. Four balls are chosen with replacement from this box. Find the probability of 3 red balls chosen.
A box contains 5 red and 15 green balls. Four balls are chosen without replacement from this box. Find the probability of 3 red balls chosen.
If a discrete random variable has an expected value E(X)=12 and a standard deviation of 2 determine E(2X-4) and Var(2X-4).
Determine which one is the example of Bernoulli trial.
Which following is not the condition for binomial distributions?
Calculate the mean and variance of rolling a '4' on a 6 sided die.
A binomial distribution has a mean of 360 and a standard deviation of 12. Find n and p.
An electrical company produces switches which are packed in boxes each containing 20 switches. It is known that 4% of switches produced are defective. Find the probability that a randomly selected box has no more than one defective switch.
The probability that John is late for school on any school day is 0.4 and it is independent of other days. For a school week of five days, find the mean number of days he will be late.
80% of all cats in a certain city have been bio-chipped. Fifty cats were randomly selected. Calculate the probability that at least 38 but no more than 42 have been bio-chipped.
In a sample of 20 cats from this city, 15 were found to have been bio-chipped, while the other 5 have not been bio-chipped. 5 cats were chosen from this sample. Calculate the probability that all five cats have been bio-chipped.
Police set up a roadblock to check cars for seatbelt use. From experience, they estimate that 80% of drivers wear seat belts. What is the probability that the second unbelted driver is in the 8th car stopped?
Which one is not discrete random variables?
A uniform continuous random variable X is defined over the interval 0 to 140 inclusive. Determine E(X) and Var(X).
The travelling time between Perth and Bunbury is uniformly distributed between 90 and 120 minutes. Calculate the probability the travelling time will be exactly 100 minutes.
The waiting time for a bus is a uniform distribution. A bus departs every 40 minutes from the bus stop. Calculate the probability that a passenger waits more than 15 minutes for the bus to depart.
X is uniform distribution over 57 to 67 inclusive. 3 observations of X were taken. Find the probability none of these observations exceed 58.
Which of these are not conditions for continuous random variable X?
The life span of light bulb is normally distributed with a mean of 800 hours and a variance of 14400 hours. Find the probability that a randomly chosen light bulb has a life span that is less than 900 hours given that it exceeds 700 hours.