The time taken to complete a particular task is normally distributed with a standard deviation of 15 minutes. A random sample of 8 people is selected and they complete the task in the following times (in minutes):
| 99 | 70 | 75 | 106 | 59 | 106 | 64 | 98 |
We use a 5% level of significance to test the claim that the mean time for completion of the task is 1 hour and 5 minutes.
The value of the test statistic is
z = -3.70
t = -3.70
z = 3.70
t = 3.70
The p-value is
| 1. p-value > 0.05 | 2. p-value < 0.05 |
Based on this evidence, the best conclusion is Answer A. Reject H0. The mean could be 65 B. Don't Reject H0. The mean could be 65 C. Reject H0. The mean is significantly more than 65. D. Don't Reject H0. The mean is significantly more than 65 E. Reject H0. The mean is significantly less than 65. F. Don't Reject H0. The mean is significantly less than 65. (select one)
Below are the null and alternative Hypothesis,
Null Hypothesis, H0: μ = 65
Alternative Hypothesis, Ha: μ ≠ 65
Test statistic,
z = (xbar - mu)/(sigma/sqrt(n))
z = (84.63 - 65)/(15/sqrt(8))
z = 3.7
P-value Approach
P-value = 0.0002
As P-value < 0.05,
reject the null hypothesis.
C. Reject H0. The mean is significantly more than 65.
The time taken to complete a particular task is normally distributed with a standard deviation of...
The health of employees is monitored by periodically weighing them in. A sample of n = 54 employees has a mean weight of x̄ = 190 lb. Assuming that σ = 25 lb, use a 0.01 significance level to test the claim that the population mean of all such employees weights is less than 200 lb. Group of answer choices a. H0: μ = 200; H1: μ < 200; Test statistic: z = -2.94. P-value: 0.0016. Since the P-Value is...
In a random sample of 84 coffee shops in Vancouver, it is found that a latte costs an average of $4.65 with a standard deviation of $0.30. Using alpha = 0.05, determine if the average price is significantly higher than $4.50. 1.Fill in the blanks to construct the correct null and alternate hypotheses. H0: [ Select ] ["p", "p-hat", "μ", "y-bar"] ...
A sample of 37 observations is selected from a normal population. The sample mean is 29, and the population standard deviation is 5. Conduct the following test of hypothesis using the 0.05 significance level. H0 : μ ≤ 26 H1 : μ > 26 a. Is this a one- or two-tailed test? "One-tailed"-the alternate hypothesis is greater than direction. "Two-tailed"-the alternate hypothesis is different from direction. b. What is the decision rule? (Round your answer to 3 decimal places.)...
A sample of size 100, taken from a population whose standard deviation is known to be 8.90, has a sample mean of 51.16. Suppose that we have adopted the null hypothesis that the actual population mean is greater than or equal to 52, that is, H0 is that μ ≥ 52 and we want to test the alternative hypothesis, H1, that μ < 52, with level of significance α = 0.05. a) What type of test would be appropriate in...
Required information [The following information applies to the questions displayed below.] A recent national survey found that high school students watched an average (mean) of 6.6 DVDs per month with a population standard deviation of 1.00 hour. The distribution of DVDs watched per month follows the normal distribution. A random sample of 30 college students revealed that the mean number of DVDs watched last month was 6.00. At the 0.05 significance level, can we conclude that college students watch fewer...
1. X is normally distributed with mean 30 and standard deviation 2.5 a) P(X > 33) = Answer b) P(X < 32) = Answer c) P(32 < X < 33) = Answer d) What value of X cuts off the top 10% of the distribution X=Answer e) What value of X cuts off the bottom 16% of the distribution X=Answer 2. A recent article in the Daily Telegraph newspaper reported that only one in five new college graduates are able to...
A recent national survey found that high school students watched an average (mean) of 7.6 movies per month with a population standard deviation of 0.5. The distribution of number of movies watched per month follows the normal distribution. A random sample of 41 college students revealed that the mean number of movies watched last month was 7.0. At the 0.05 significance level, can we conclude that college students watch fewer movies a month than high school students? State the null...
A recent national survey found that high school students watched an average (mean) of 7.1 movies per month with a population standard deviation of 1.0. The distribution of number of movies watched per month follows the normal distribution. A random sample of 41 college students revealed that the mean number of movies watched last month was 6.6. At the 0.05 significance level, can we conclude that college students watch fewer movies a month than high school students? State the null...
A recent national survey found that high school students watched an average (mean) of 7.8 movies per month with a population standard deviation of 0.5. The distribution of number of movies watched per month follows the normal distribution. A random sample of 30 college students revealed that the mean number of movies watched last month was 7.3. At the 0.05 significance level, can we conclude that college students watch fewer movies a month than high school students? State the null...
The lengths of major league baseball games are approximately normally distributed and average 2 hours and 50.1 minutes (170.1 minutes), with a population standard deviation of 18 minutes. It has been claimed that New York Yankee baseball games last, on the average, longer than the games of the other major league teams. To test the truth of this statement, a sample of eight Yankee games were randomly identified and the "time of the game" (in minutes) for each obtained. 199...