# normal approximation to the binomial distribution questions and answers

SURVEY . When the Normal Distribution may be used to approximate a binomial distribution. because we are going to use a continuous distribution to approximate a discrete one, we have to apply continuity correction, by which "at least 30" becomes "at least 29.5" z-score = (29.5 - 24)/4.85 = 1.13 to 2 dp. a fair coin is tossed 10 times, find the probability of getting between 3 and 6 heads inclusive using: the normal approximation to the binomial distribution. This can be closely approximated by using a normal distribution with mean = n*p = 57.6 and standard deviation = sqrt(n*p*(1 - p)) = 7.475 (3dp). We and our partners will store and/or access information on your device through the use of cookies and similar technologies, to display personalised ads and content, for ad and content measurement, audience insights and product development. Suppose we take a sample of 200 adults. It gives reliable approximation and as sample size increases, the reliability also increases. For a binomial variable X, the z statistic computed as (X - mean) / standard deviation. Compare your results with values obtained from Table I of App. A normal distribution with mean 25 and standard deviation of 4.33 will work to approximate this binomial distribution. Hence, normal approximation can make these calculation much easier to work out. Fourteen percent of all students at a large university are absent on Mondays. If a random sample of 11 names is called on a Monday, what is the probability that four students are absent? Use the normal distribution as an approximation to the binomial distribution to solve this problem. Translate the problem into a probability statement about X. John is taking a test consisting of 60 true/false questions. Browse other questions tagged normal-distribution binomial approximation or ask your own question. The experiment must have a fixed number of trials 2. If all the answers are random guesses, calculate the probability of obtaining at least 20% of correct answers. stream 0.071 A multiple choice test has a probability any question will be guesses correctly of 0.25. Exam Questions – Normal approximation to the binomial distribution. • Fill in the boxes at the top of this page with your name. Each trial must have all outcomes classified into two categories 4. The Normal distribution is used to approximate Binomial distribution when sample size is large enough. (a) What is the probability that at least 175 adults like chocolate? • If pencil is used for diagrams/sketches/graphs it must be dark (HB or B). Find out more about how we use your information in our Privacy Policy and Cookie Policy. Normal probability distribution is the base of statistical inference and it is widely used in statistical inference and interpretation. Remember that when going from the binomial (which is a discrete distribution) to the normal (which is a continuous one) you should apply the continuity correction and look for P(x > 64.5). expected successes are n * p > 10 Calculate the following probabilities using the normal approximation to the binomial distribution, if possible. Statistics Q&A Library Normal Approximation to the Binomial Distribution: In a recent survey, we found that 85% of adults like chocolate. Conditions for using the formula. The probabilities must remain constant for each trial. 1) View Solution. This is very useful for probability calculations. Yahoo is part of Verizon Media. Assuming that a normal distribution is a reasonable approximation for a binomial distribution, what … On this page you will learn: Binomial distribution definition and formula. reqd. 3 examples of the binomial distribution problems and solutions. When the Normal Distribution may be used to approximate a binomial distribution. 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