Answer:
To determine the test statistic for this problem, we need to first calculate the standard error of the mean. This is given by the formula:
Standard error of the mean = Standard deviation / sqrt(n)
where n is the number of samples in the population. In this case, the standard deviation is 1 minute and the number of samples is 20, so the standard error of the mean is equal to 1 / sqrt(20) = 0.22.
We can now use this value to calculate the test statistic, which is given by the formula:
Test statistic = (Sample mean - Population mean) / Standard error of the mean
In this case, the sample mean is 3.7 minutes, the population mean is less than 3.5 minutes, and the standard error of the mean is 0.22. Since the population mean is less than 3.5 minutes, we will use 3.5 as the value for the population mean in our calculation. Plugging these values into the formula, we get:
Test statistic = (3.7 - 3.5) / 0.22 = 0.22 / 0.22 = 1
Therefore, the test statistic for this problem is 1. This value indicates that the sample mean is slightly higher than the population mean, but not by a significant amount.