Final Answer:
The p-value for the test at
is less than 0.05; therefore, we reject the null hypothesis.
Therefore, option a) 0.05 is correct.
Step-by-step explanation:
To assess whether the data refutes the manufacturer's claim, conduct a one-sample t-test. With a sample mean of 79.7%, a claimed mean of 80%, a sample size of 100, and a standard deviation of 0.8%, calculate the t-statistic.
Using the formula
, where
is the sample mean,
is the claimed mean, s is the standard deviation, and n is the sample size, we find the t-value. Then, find the p-value associated with the t-value.
With the calculated p-value, compare it to the significance levels
of 0.05, 0.01, 0.10, and 0.20. If the p-value is less than
, it suggests that there is sufficient evidence to reject the null hypothesis. In this case, the p-value at
is less than 0.05, leading to the rejection of the null hypothesis.
Therefore, option a) 0.05 is correct.