(1) The average number of humming birds per hour on a particular feeder is 5. Find the probability that exactly 3 humming birds feed during a particular hour using the correct table or formula.

(2) Weights for students applying to a Sumo wrestling school are normally distributed, with a mean of 250 pounds and a standard deviation of 25 pounds. To be eligible to enter, a person must weight in the top 15%. What is the lowest weight a student can have and still be eligible to enter the school.

(3) Determine the minimum required sample size if you want to be 95% confident that the sample mean is within 2 units of the true population mean. Assume that sigma = 7.8 is known and that the population is normally distributed.

(4) A horticulturalist wants to study the growth rate of a particular variety of Bougainvillea. From a sample of 16 randomly selected Bougainvilleas, the mean growth rate was 2.23 inches/week and the sample standard deviation was 0.77 inches/week. Find a 90% confidence interval for the mean growth rate of all Bougainvilleas.

Solution Summary

The solution gives step by step method for calculation of probability from normal distribution using z score.

... for the IRS site computed in Problem 6.52 to ...Normal Probabilities (a) Normal Probabilities (b). ... Mean Standard Deviation 0.5 Standard Deviation Probability for ...

... and standard deviation =0.9375 4.) Find the mean and standard error of the ... step by step method for the calculation of probability for normal distribution . ...

... Statistic problems 1. Find the following probabilities: ... cumulative X p(X) probability 0 0.88638 0.88638 1 0.10744 ... 6. X has a normal distribution with a mean of ...

... µ X − 16.5 Using Z = and standard normal table we cal calculate the probabilities = 3.5 σ. ... P[X=18.00] = 0 (For continues distribution , probability at a ...

Normal Probabilities - Solving Problems Using Z Score. ... a randomly selected morning what is the probability that the ... IQ scores form a normal distribution with µ ...

Normal distribution, probabilities (3 problems). Problem 1. ... Calculate the probability that an adult will have. a ) IQ less than 100. b) IQ greater than 150. ...

... (A) Determine the maximum error of the ... provides step by step method for the calculation of confidence interval for mean, sample size and normal probability. ...

... distribution is not known, we cannot calculate probability. Uses Excel for calculating probabilities in a Normal Distribution. hw07 Problem 9.13 and 9.14. ...