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If Z is a standard normal variable, find the probability. P(Z > 0.59)

Find the indicated probability. The incomes of trainees at a local mill are normally distributed with a mean of $1100 and a standard deviation $150. What percentage of trainees earn less than $900 a month?

Batteries of a certain type have voltages that are normally distributed with a mean of 13.9 volts and a standard deviation of 1.2 volts. If one battery is randomly selected, what is the probability that it yields less than 13.0 volts?P(x < 13.0) =

Match the following symbols:

Suppose X ~ N([a], [b]). What value of x has a z-score of [c]? (Round to 2 decimal places as needed.)  

A machine which produces a major part for an airplane engine is monitored closely. In the past, 10% of the parts produced are defective. With a 95% confidence, what is the the sample size that needs to be taken if the desired sampling error is 5% or less. Round appropriately.

The scores on a college entrance exam have an approximate normal distribution with mean, µ = 52 points and a standard deviation, σ = 11 points. Find the following using the empirical rule. About 68% of the y values lie between [a1] points and [a2] points.  

Identify the null hypothesis H0 and the alternative hypothesis HA. Use μ for a claim about a mean and p for a claim about a proportion.A cereal company claims that the mean weight of the cereal in its packets is at least 14 oz.

Use the confidence level and sample data to find the margin of error, E, for the mean. 95% confidence, n = 8, sample mean = 38.0, and s = 9.7 (Assume the data has a normal distribution.)

Solve the problem. Find the critical value that corresponds to a degree of confidence of 91%.