/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 34 The distribution of red blood ce... [FREE SOLUTION] | 91Ó°ÊÓ

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The distribution of red blood cell counts is different for men and women. For both, the distribution is approximately Normal. For men, the middle \(95 \%\) range from \(4.5\) to \(5.7\) million cells per microliter and for women, the middle \(95 \%\) have red blood cells counts between \(3.9\) and \(5.0\) million cells per microliter. a. What is the mean and the standard deviation of red blood cell counts for men? Explain your reasoning. b. What is the mean and the standard deviation of red blood cell counts for women? Explain your reasoning. c. Which gender shows more variation in red blood cell counts? Support your answer with appropriate statistics.

Short Answer

Expert verified
The mean red blood cell count for men is \(5.1\) million cells per microliter with a standard deviation of \(0.3\), while for women the mean is \(4.45\) million cells per microliter with a standard deviation of \(0.275\). Men show a greater variation in red blood cell counts as their standard deviation is higher.

Step by step solution

01

Calculate the Mean and Standard Deviation for Men

The middle 95% of men's red blood cell counts ranges from 4.5 to 5.7 million cells per microliter. Therefore, the mean is the mid-point of this range, calculated as \((4.5 + 5.7) / 2 = 5.1\). The standard deviation is found by dividing the range by 4 (due to the 95% rule), resulting in \((5.7 - 4.5) / 4 = 0.3\).
02

Calculate the Mean and Standard Deviation for Women

Following the same procedure, for women, the mean is found to be \((3.9 + 5.0) / 2 = 4.45\) and the standard deviation is \((5.0 - 3.9) / 4 = 0.275\).
03

Compare the Variations

The standard deviation represents the measure of variation. Comparing the standard deviations of both genders, it is evident that the standard deviation for men \(0.3\) is higher than that for women \(0.275\). Thus, men show more variation in red blood cell counts compared to women.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Mean and Standard Deviation
Understanding the mean and standard deviation within the context of normal distribution is fundamental in statistics. The mean provides us with the central value of a data set, offering a quick glimpse into what might be considered 'typical' for that set. In the case of red blood cell counts, the mean is determined by finding the midpoint within the given normal range.

For men, this midpoint is calculated by adding the lower limit of the normal range (\(4.5\text{ million cells per microliter}\)) to the upper limit (\(5.7\text{ million cells per microliter}\)) and dividing by 2, yielding a mean of \(5.1\text{ million cells per microliter}\).

The standard deviation, on the other hand, quantifies the amount of variation or dispersion of a set of data values. A low standard deviation indicates that the data points tend to be close to the mean, whereas a high standard deviation indicates that the data points are spread out over a wider range of values. For men, by using the range rule for standard deviation, which is applicable in a normally distributed data set, we divide the range (difference between the upper and lower limits of normal) by 4. This calculation results in a standard deviation of \(0.3\text{ million cells per microliter}\) for the red blood cell counts of men.
Red Blood Cell Counts
Red blood cell (RBC) counts are a vital component of a complete blood count (CBC), providinhttp://localhost/knowledge/tasks/44327#g a measure of the number of red blood cells in a specific volume of blood. These measurements are significant as they can indicate a range of health conditions from anemia to polycythemia. Normal values vary based on demographics, including gender.

For women, calculations are similar to those for men. The mean RBC count for women is at the midpoint of the normal range, \((3.9 \plus 5.0) / 2 = 4.45\) million cells per microliter. In biological terms, these differences are significant and tie into various physiological factors such as hormonal levels and iron metabolism, which could contribute to the discrepancies in normal RBC count ranges between genders.

Standard deviation in this context is also a significant indicator of health. A woman with an RBC count falling far outside the standard deviation might be considered to have a condition warranting further investigation.
Statistical Variation
Statistical variation encompasses how much individual data points in a set deviate from the mean. This variation is an essential piece of understanding statistical distributions and is often visualized through graphs like bell curves in the context of normal distribution.

In terms of red blood cell counts, statistical variation can provide insights into the health disparities between men and women. As reported in the exercise, men have a higher standard deviation, indicating a greater spread of RBC counts around the mean, which can suggest a higher degree of variability in the male population's physical characteristics or health conditions.

Evaluating health risks or diagnosing conditions often relies on understanding this variability. Clinicians and researchers can use measures of statistical variation to assist in creating norms and identifying outliers, ultimately aiding in better personalized healthcare.

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