Main Answer:
The x interval 4.5 corresponds to a red blood cell count of approximately 4.5 million per cubic millimeter of whole blood for healthy females, based on an approximately normal distribution with a mean of 5.3 million per cubic millimeter and a standard deviation of 0.5 million per cubic millimeter.
Explanation:
When working with normally distributed data, it can be helpful to convert raw values into standardized scores, known as z-scores, which represent the number of standard deviations a value is above or below the mean.
In this case, we can use the formula z = (x - μ) / σ to calculate the z-score corresponding to an RBC count of 4.5 million per cubic millimeter for healthy females.
Substituting our given values into the formula, we get:
z = (4.5 - 5.3) / 0.5
z = -2.1
This tells us that an RBC count of 4.5 million per cubic millimeter is approximately 2.1 standard deviations below the mean for healthy females.
Using a standard normal distribution table, we can determine that this corresponds to a probability of approximately 0.023, or less than 3 out of every 100 healthy females would be expected to have an RBC count this low.
This indicates that an RBC count of 4.5 million per cubic millimeter is considered to be outside the normal range for healthy females and may be indicative of a medical condition requiring further investigation and treatment.