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 probability that one randomly selected person learned to walk when the person was between 11 and 13 months old? I

Step 1 ：Given that the age that children learn to walk is normally distributed with a mean (\(\mu\)) of 12 months and a standard deviation (\(\sigma\)) of 1.3 months.

Step 2 ：We are asked to find the probability that a randomly selected person learned to walk between 11 and 13 months old.

Step 3 ：This is a problem of normal distribution. We can use the Z-score formula to standardize the values and then use the standard normal distribution table to find the probability.

Step 4 ：The Z-score formula is: \(Z = \frac{X - \mu}{\sigma}\), where X is the value we are standardizing.

Step 5 ：We will need to calculate two Z-scores, one for 11 months and one for 13 months, and then find the difference in the cumulative probabilities for these two Z-scores.

Step 6 ：Calculating the Z-scores: \(Z_{11} = \frac{11 - 12}{1.3} = -0.7692\) and \(Z_{13} = \frac{13 - 12}{1.3} = 0.7692\)

Step 7 ：Using the standard normal distribution table, we find the cumulative probabilities for these Z-scores: \(P_{11} = 0.2209\) and \(P_{13} = 0.7791\)

Step 8 ：The probability that a randomly selected person learned to walk between 11 and 13 months old is the difference in these probabilities: \(P = P_{13} - P_{11} = 0.7791 - 0.2209 = 0.5582\)

Step 9 ：Final Answer: The probability that one randomly selected person learned to walk when the person was between 11 and 13 months old is approximately \(\boxed{0.5582}\).