Suppose the age that children learn to walk is normally distributed with mean 12 months and standard deviation 1.3 month. 17 randomly selected people were asked what age they learned to walk. Round all answers to 4 decimal places where possible. What is the distribution of $x^{-} x^{-}$

Step 1 ：The problem is asking for the distribution of the sample mean, denoted as \(x^{-}\).

Step 2 ：We know that the distribution of the sample mean follows a normal distribution with mean equal to the population mean and standard deviation equal to the population standard deviation divided by the square root of the sample size. This is a result of the Central Limit Theorem.

Step 3 ：The given population mean (mu) is 12 months and the population standard deviation (sigma) is 1.3 months. The sample size (n) is 17.

Step 4 ：The mean of the sample mean distribution (mu_x_bar) is the same as the population mean, which is 12 months.

Step 5 ：The standard deviation of the sample mean distribution (sigma_x_bar) is the population standard deviation divided by the square root of the sample size, which is approximately 0.3153 months.

Step 6 ：Final Answer: The distribution of the sample mean \(x^{-}\) is normally distributed with mean \(\boxed{12}\) months and standard deviation \(\boxed{0.3153}\) months.