Since population SD is known and we are comparing the population means, a two tailed z test will be used.
Test statistic: (197-196)/√(4^2 +2^2)/130= 2.550
P-value of this two sided z test:
2*P(z>2.55) = 0.0108
(From the standard normal distribution tables)
Since the p-value of this test > significance level of 0.01, we have insufficient evidence to Reject H0. So we fail to conclude that the voltage of batteries of different manufacturers are different.
CHALLENGE ACTIVITY 5.7.1: Hypothesis test for the difference between two population means. Jump to level 1...
CHALLENGE ACTIVITY 5.7.1: Hypothesis test for the difference between two population means. > Jump to level 1 The mean voltage and standard deviation of 5 batteries from each manufacturer were measured. The results are summarized in the following table. Manufacturer Sample mean voltage (millivolts) Sample standard deviatio A 167 B 164 3 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 What is the number of degrees of freedom? Ex 250 Does sufficient...
CHALLENGE ACTIVITY 5.7.1: Hypothesis test for the difference between two population means. Start An electrician wants to know whether batteries made by two manufacturers have significantly different voltages. The voltage of 95 batteries from each manufacturer were measured. The population standard deviations of the voltage for each manufacturer are known. The results are summarized in the following table. D-D-D- 3 Manufacturer Sample mean voltage (millivolts) Population standard deviat A 125 5 B 124 3 What type of hypothesis test should...
Jump to level 1 The mean voltage and standard deviation of 17 batteries from each manufacturer were measured. The results are summarized in the following table. 2 Manufacturer Sample mean voltage (millivolts) Sample standard deviatio А 171 B 169 3 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 What is the number of degrees of freedom? Ex 250 Does sufficient evidence exist to support the claim that the voltage of the batteries...
Jump to level 1 2 The mean voltage and standard deviation of 5 batteries from each manufacturer were measured. The results are summarized in the following table. Manufacturer Sample mean voltage (millivolts) Sample standard deviatio 3 А 126 5 B 119 4 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 0 What is the number of degrees of freedom? Ex: 259 Does sufficient evidence exist to support the claim that the voltage...
< Jump to level 1 The mean voltage and standard deviation of 7 batteries from each manufacturer were measured. The results are summarized in the following table. 2 3 Manufacturer Sample mean voltage (millivolts) Sample standard deviatio A 161 3 B 157 2 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 0 What is the number of degrees of freedom? Ex 250 Does sufficient evidence exist to support the claim that the...
Jump to level 1 The mean voltage and standard deviation of 14 batteries from each manufacturer were measured. The results are summarized in the following table. Manufacturer Sample mean voltage (millivolts) Sample standard deviatio A 173 4 B 170 2 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 What is the number of degrees of freedom? Ex: 250 Does sufficient evidence exist to support the claim that the voltage of the batteries...
im stuck at finding the number of degrees of freedom Jump to level 1 The mean voltage and standard deviation of 17 batteries from each manufacturer were measured. The results are summarized in the following table. 3 Manufacturer Sample mean voltage (millivolts) Sample standard deviatio A 171 2 B 169 3 What type of hypothesis test should be performed? Two-tailed z-test What is the test statistic? 2.550 What is the number of degrees of freedom? Ex: 250 Does sufficient evidence...
The mean voltage and standard deviation of 13 batteries from each manufacturer were measured. The results are summarized in the following table. 2 3 Manufacturer Sample mean voltage (millivolts) Sample standard deviatio A 131 1 B 127 4 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 What is the number of degrees of freedom? Ex 250 Does sufficient evidence exist to support the claim that the voltage of the batteries made by...
The mean voltage and standard deviation of 10 batteries from each manufacturer were measured. The results are summarized in the following table. Manufacturer Sample mean voltage (millivolts) Sample standard deviatio A 160 4 . В 158 2 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 What is the number of degrees of freedom? Ex: 250 Does sufficient evidence exist to support the claim that the voltage of the batteries made by the...
The null and alternative hypotheses for a hypothesis test of the difference in two population means are: Null Hypothesis: Alternative Hypothesis: Notice that the alternative hypothesis is a two-tailed test. Suppose ttest_ind method from scipy module is used to perform the test and the output is (-1.99, 0.0512). What is the P-value for this hypothesis test? Select one. Question 4 options: 0.0512 1.99 0.0256 -1.99