When is it appropriate to use the two-sample t-methods instead of the one sample t-methods? Choose the correct answer below. A
. Use the two-sample t-methods when a sample was taken from each of two populations (i.e. two groups being compared) and the population standard deviations are not known. Use the one-sample t-methods when a sample was taken from one population. B. Use the two-sample t-methods when a random sample was not taken. Use the one-sample t-methods when a random sample was taken. C. Use the two-sample t-methods when the conditions for inference using the one-sample t-methods aren't satisfied. D. Use the two-sample t-methods when the population standard deviation is known. Use the one-sample t-methods when the population standard deviation is not known.
A. Use the two-sample t-methods when a sample was taken from each of two populations (i.e. two groups being compared) and the population standard deviations are not known.
Step-by-step explanation:
T-distribution:
When the population standard deviation is not known, the t-distribution is used.
If a sample was taken from one population, we use the one-sample method, while if there is a comparison of two populations, the two-sample method is used, and thus, the correct answer is given by option A.
