Step 1 :We are given a population of values with a normal distribution, where the mean (\(\mu\)) is 221.4 and the standard deviation (\(\sigma\)) is 29.7.
Step 2 :We are asked to find the probability that a single randomly selected value is between 225.5 and 226.3.
Step 3 :To solve this, we need to standardize the values 225.5 and 226.3 using the formula: \[Z = \frac{X - \mu}{\sigma}\] where X is the value, \(\mu\) is the mean and \(\sigma\) is the standard deviation.
Step 4 :Substituting the given values into the formula, we get: \[Z_1 = \frac{225.5 - 221.4}{29.7} = 0.138\] and \[Z_2 = \frac{226.3 - 221.4}{29.7} = 0.165\]
Step 5 :We can then use the standard normal distribution (Z-distribution) to find the probabilities. The probability for \(Z_1\) is 0.555 and for \(Z_2\) is 0.566.
Step 6 :The probability that a single randomly selected value is between 225.5 and 226.3 is the difference between these two probabilities, which is \(0.566 - 0.555 = 0.011\).
Step 7 :Rounding to four decimal places, the final answer is \(\boxed{0.0106}\).