The Standard Normal Distribution - Page 2

Questions
  • How do you find #z# so that 82% of the standard normal curve lies to the right of #z#?
  • What is the area under the standard normal curve to the right of z = 1.43?
  • Suppose that 40% of adult email users say "Yes." A polling firm contacts an SRS of 1500 people chosen from this population. If the sample were repeated many times, what would be the range of sample proportions who say "Yes"?
  • How do you find the area under the standard normal curve that lies to the right of z = 2.01?
  • How do you find the area under the standard normal curve that lies between z = -1.00 and z = -1.10?
  • What's the percentage of area under a normal curve between the mean and -.90 standard deviations below the mean?
  • What is the area under the normal curve between z = -1.0 and z = -2.0?
  • The time required to finish a test is normally distributed (i.e. in a Gaussian distribution) with a mean of 60 minutes and a standard deviation of 10 minutes. What is the probability that a student will finish the test in less than 70 minutes?
  • The mean score for a standardized test is 1700 points. The results are normally distributed with a standard deviation of 75 points. If 10,000 students take the exam, how many would you expect to score between 1700 and 1775 points?
  • The time required to finish a test is normally distributed with a mean of 60 minutes and a standard deviation of 10 minutes. What is the probability that a student will finish the test between 50 and 60 minutes?
  • What is the the area under the standard normal curve between z = -2.49 and z = -0.57?
  • What is the area under the standard normal curve between z = .84 and z = 1.95?
  • The resting heart rates for a sample of individuals are normally distributed with a mean of 70 and a standard deviation of 15. How do you find the percentage of heart rates less than 85?
  • Use the standard normal distribution to find #P(z lt 1.96)#.
  • Given that #z# is a standard normal random variable, what is the value of #z# if the area to the right of #z# is 0.1112?
  • What is #P (Z< -2.12)#?
  • Does the standard error of the mean show how close the sample mean is from the population mean?
  • If the variance of the data values in a sample is 225, what is the standard deviation of the data values?
  • Given that #z# is a standard normal random variable, what is the value of #z# if the area to the right of #z# is .1401?
  • How can I tell if my data is normally distributed? Do the mean, median and mode have to be identical for it to be a normal distribution?