Which sample size gives a smaller standard error of the mean according to Central Limit theorem?
a. 10 b. 15 c. 25 d. 35
D. 35
What is the other term for t-distribution?
a. Z-distribution b. Probability distribution
c. Percentile distribution d. Student’s t-distribution
D.
This refers to the maximum number of logically independent values which varies in the data sample.
a. Level of significance b. Percentiles
c. Degree of freedom d. Probability
C
What test should be utilized if an economist wishes to determine whether there is evidence that the average family income in a community exceeds P15,000?
A. A two-tail test should be utilized.
B. A one-tail test should be utilized to the left.
C. A one-tail test should be utilized to the right.
D. Either one tail or two-tai test could be used with equivalent results.
C
The average test score of the entire school is 78 with standard deviation 10. A teacher took a random sample of 10 students and scored 75? What is the sample mean?
A. 8 B. 10 C. 75 D.78
C. 75
What is the level of significance if the confidence interval is 90%?
10% or 0.10
What is the critical value/s of α= 0.05 in a two-tailed test?
±1.960
What will be the degree of freedom of the data with a sample size of 20?
19
Which of the following terms should be used to complete the statement, “In a two-sample test of means for independent samples, the equal sign always appears in the ____________.”?
Null Hypothesis
What statistical concept am I? alpha
level of significance or margin of error
When is a Type I error committed?
A. We reject a null hypothesis that is false.
B. We reject a null hypothesis that is true.
C. We fail to reject a null hypothesis that is true.
D. We fail to reject a null hypothesis that is false.
B
The mean gasoline consumption of 10 cars is 28 liters with a standard deviation of 1.6 liters. Find the point and the interval estimates using 95% confidence level. What is 𝛼 or level of significance?
5%
The mean of the sampling distribution of the sample means according to the Central Limit Theorem is __________.
a. exactly equal to the population mean.
b. close to the population means if the sample size is large.
c. equal to the population mean divided by the square of the sample size.
d. cannot be determined
A
An education official wants to estimate the proportion of adults aged 18 and above who had read at least one book during the previous year. A random sample of 1,006 adults aged 18 or older is obtained, and 835 of those adults had read at least one book during the previous year. Determine the parameter in the situation.
The parameter is the proportion of adults who had read at least one book during the previous year.
What is the test statistic when the population mean is 0.610, the sample mean 0.587, standard deviation is 0.123 and the number of samples is 40?
z=-1.18
Milky Milk is sold in packets with an advertised mean weight of 0.5kgs. The standard deviation is known to be 0.11 kilograms. A consumer group wishes to check the accuracy of the advertised mean and takes a sample of 36 packets finding an average weight of 0.47kgs. What test statistic should be used?
Z test
The Central Limit Theorem says that the sampling distribution of the sample mean is approximately normal if __________.
a. the sample size is large.
b. all possible samples are selected.
c. the standard error of the sampling mean is small.
d. none of the above
A
This refers to the measure of position whose data is divided into 100 parts.
Percentile
The mean height of women is less than 64(inches). State the null and alternative hypotheses.
H0: μ ≥ 64; Hₐ: μ < 64
In a study about household income conducted in a small town, it was found that 7% of all families in the town earn less than P4,000 per month. Out of 64 families who were randomly selected, 10 families earn less than P4,000 per month. Is the sample large enough to use the Central Limit Theorem?
yes, n>30
When is the null hypothesis rejected?
If the test-statistic value falls within the rejection region
The average test score of entire school is 78. The random sample of 32 with standard deviation 9. The average test score of the sample is 84. Find the z-value.
z=3.77
What is the critical value of 0.01 level of significance when the alternative hypothesis indicates ≠?
±2.575
Which directional test is illustrated in the given problem below?
In a recent survey, the average amount of money students has in their wallet is ₱200.00 with standard deviation of 45. A teacher feels that the average amount is lower. She surveyed 80 randomly selected students and found that the average amount is ₱35.
Left-tailed
A tire manufacturer claims that its tires have a mean life of 40,000 km. A random sample of 46 of these tires is tested and the sample mean is 38,000 km. Assume that the population’s standard deviation is 2,000 km and the lives of tires are approximately normally distributed. What is the computed value at 5% level of significance?Answer in 3 decimal places
z=--6.782