Assuming normal speed distribution, if d is defined as +2 km/h, standard deviation is as 5km/h,...
A normal probability distribution a. has a standard deviation of 0. O b. must have a standard deviation of 1 and a mean of 0. c. needs to have a mean of 0. d. can have mean of any numerical value.
(H) FALSE Which of the following statisties describes the spread of the normal distribution? (a) mean (b) minimum (e) maximum (d) standard deviation (e) none of the above
Traffic police monitor the speed of vehicles as they travel over a new bridge. The average speed for a sample of 31 vehicles was 82.72 km/h, with the sample standard deviation being 4.61 km/h. We will assume that the speeds are Normally distributed, and the police are interested in the mean speed. Part a) Since the variance of the underlying Normal distribution is not known, inference here would involve the t distribution. How many degrees of freedom would the relevant...
Traffic police monitor the speed of vehicles as they travel over a new bridge. The average speed for a sample of 27 vehicles was 91.29 km/h, with the sample standard deviation being 4.94 km/h. We will assume that the speeds are Normally distributed, and the police are interested in the mean speed. Part a) Since the variance of the underlying Normal distribution is not known, inference here would involve the t distribution. How many degrees of freedom would the relevant...
Questions 12–14. Random variable X follows a normal distribution with mean 60 and standard deviation 10. 12. The 10th percentile of X is closest to (a) 24.5 (b) 34.2 1(c) 47.2 (d) 52.7 (e) 58.3 13. Which one of the following probabilities is equal to P(40 < X < 48)? J(a) P(72 < X < 80) (b) P(64 < X < 72) (c) P(50 < X < 58) (d) P(80 < X < 88) (e) P(56 < X < 64)...
1. Use Table A to find the proportion of observations from a standard Normal distribution that satisfies each of the following statements. In each case, sketch a standard Normal curve and shade the area under the curve that is the answer to each question. a. z<-1.83 b.z > 2.18 c. Z>-0.51 d. z <0.33 e. 1.42<z <2.68 f.-2 <2<1.53 X is a normally distributed variable with mean u = 30 and standard deviation o = 4. Find the following: a....
A sample from a Normal distribution with an unknown mean u and known variance o = 45 was taken with n=9 samples giving sample mean of y = 3.6. (a) Construct a Hypothesis test with significance level a = 0.05 to test whether the mean is equal to 0 or it is greater than 0. What can you conclude based on the outcome of the sample? (b) Calculate the power of this test if the true value of the mean...
6. A normal distribution of has a mean of 20 and a standard deviation of 10. Find the z-scores corresponding to each of the following values: (10 points) a) What is the z score for a value of 30? b) What is the z score for a value of 10? c) What is the z score for a value of 15? d) What it P(20<x<30)? e) What is P (x > 10)? ) What is P (x < 15)? g)...
Question 6 1 pts The scores on Quiz 2 follows the normal distribution with a mean of 8 and a standard deviation of 0.5. (Round your answers to two decimal places). What is the probability that a randomly selected student has a score above 8? 0.95 0.05 O.50 0.45
Given a standardized normal distribution with mean - 0 and standard deviation 1: d. What is the Z value that corresponds to a cumulative probability (from -oo to Z) of 0.3368? e. What is the Z value that corresponds to a cumulative probability (from -oo to Z) of 0.5832? f. What is the Z value that corresponds to a cumulative probability (from -oo to Z) of 0.7500? g. What is the Z value that corresponds to a cumulative probability (from...