21. If U is uniformly distributed on (0, 1), show that a + (b- a)U is uniform on (a, b). 22. You arrive at a bus stop at 10 o'clock, knowing that the bus will arrive at some time uniformly distributed between 10 and 10:30. What is the probability that will have to wait longer than 10 minutes? If at 10:15 the bus has not yet you arrived, what is the probability that you will have to wait at least an additional 10 minutes? 23. If X is a normal random variable with parameters u = 10, o = 36, compute %3D %3D fa P{X > 5}; Ab) P{4 < X < 16}; (c) P{X < 8}; (d) P{X < 20}; (e) P{X > 16}. 24. The Scholastic Aptitude Test mathematics test scores across the population of high school seniors follow a normal distribution with mean 500 and standard deviation 100. If five seniors are randomly chosen, find the probability that (a) all scored below 600 and (b) exactly three of them scored above 640. 25. The annual rainfall (in inches) in a certain region is normally distributed with = 4. What is the probability that in 2 of the next years the u = 40, o rainfall will exceed 50 inches? Assume that the rainfalls in different years are independent. %3D 26. The weekly demand for a product approximately has a normal distribution with mean 1,000 and standard deviation 200. The current on hand inventory is 2,200 and no deliveries will be occurring in the next two weeks. Assuming that the demands in different weeks are independent, (a) what is the probability that the demand in each of the next 2 weeks is less than 1,100? (b) what is the probability that the total of the demands in the next 2 weeks exceeds 2,200? 27. A certain type of lightbulb has an output that is normally distributed with mean 2,000 end foot candles and standard deviation 85 end foot candles. Determine a lower specification limit L so that only 5 percent of the lightbulbs produced will be below this limit. (That is, determine L so that P{X > L} = .95, where X is the output of a bulb.) 28. A manufacturer produces bolts that are specified to be between 1.19 and 1.21 inches in diameter. If its production process results in a bolt's diameter being normally distributed with mean 1.20 inches and standard deviation .005, what percentage of bolts will not meet specifications?
Addition Rule of Probability
It simply refers to the likelihood of an event taking place whenever the occurrence of an event is uncertain. The probability of a single event can be calculated by dividing the number of successful trials of that event by the total number of trials.
Expected Value
When a large number of trials are performed for any random variable ‘X’, the predicted result is most likely the mean of all the outcomes for the random variable and it is known as expected value also known as expectation. The expected value, also known as the expectation, is denoted by: E(X).
Probability Distributions
Understanding probability is necessary to know the probability distributions. In statistics, probability is how the uncertainty of an event is measured. This event can be anything. The most common examples include tossing a coin, rolling a die, or choosing a card. Each of these events has multiple possibilities. Every such possibility is measured with the help of probability. To be more precise, the probability is used for calculating the occurrence of events that may or may not happen. Probability does not give sure results. Unless the probability of any event is 1, the different outcomes may or may not happen in real life, regardless of how less or how more their probability is.
Basic Probability
The simple definition of probability it is a chance of the occurrence of an event. It is defined in numerical form and the probability value is between 0 to 1. The probability value 0 indicates that there is no chance of that event occurring and the probability value 1 indicates that the event will occur. Sum of the probability value must be 1. The probability value is never a negative number. If it happens, then recheck the calculation.
Question 28
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 2 images