Because serum cholesterol is related to age and sex, some investigators prefer to express it in terms of z -scores. If X = raw serum cholesterol, then Z = X − μ σ , where μ is the mean and σ is the standard deviation of serum cholesterol for a given age–gender group. Suppose Z is regarded as a standard normal random variable. What is Pr ( Z < 0.5)?

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Answer 1

Textbook Question

Chapter 5, Problem 1P

Because serum cholesterol is related to age and sex, some investigators prefer to express it in terms of z-scores. If X = raw serum cholesterol, then Z = X − μ σ , where μ is the mean and σ is the standard deviation of serum cholesterol for a given age–gender group. Suppose Z is regarded as a standard normal random variable.

What is Pr(Z < 0.5)?

Expert Solution & Answer

To determine

Find probability P(Z<0.5).

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

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Answer 2

Textbook Question

Chapter 5, Problem 1P

Because serum cholesterol is related to age and sex, some investigators prefer to express it in terms of z-scores. If X = raw serum cholesterol, then Z = X − μ σ , where μ is the mean and σ is the standard deviation of serum cholesterol for a given age–gender group. Suppose Z is regarded as a standard normal random variable.

What is Pr(Z < 0.5)?

Expert Solution & Answer

To determine

Find probability P(Z<0.5).

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

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Answer 3

Textbook Question

Chapter 5, Problem 1P

Because serum cholesterol is related to age and sex, some investigators prefer to express it in terms of z-scores. If X = raw serum cholesterol, then Z = X − μ σ , where μ is the mean and σ is the standard deviation of serum cholesterol for a given age–gender group. Suppose Z is regarded as a standard normal random variable.

What is Pr(Z < 0.5)?

Expert Solution & Answer

To determine

Find probability P(Z<0.5).

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

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Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 4

Textbook Question

Chapter 5, Problem 1P

Because serum cholesterol is related to age and sex, some investigators prefer to express it in terms of z-scores. If X = raw serum cholesterol, then Z = X − μ σ , where μ is the mean and σ is the standard deviation of serum cholesterol for a given age–gender group. Suppose Z is regarded as a standard normal random variable.

What is Pr(Z < 0.5)?

Expert Solution & Answer

To determine

Find probability P(Z<0.5).

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

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Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 5

Textbook Question

Answer 6

Textbook Question

Answer 7

Expert Solution & Answer

To determine

Find probability P(Z<0.5).

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

Answer 8

Expert Solution & Answer

To determine

Find probability P(Z<0.5).

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

Answer 9

Expert Solution & Answer

Answer 10

Expert Solution & Answer

Answer 11

To determine

Find probability P(Z<0.5).

Answer 12

Answer to Problem 1P

Probability, P(Z<0.5), is 0.6915.

Answer 13

Explanation of Solution

Step-by step procedure to obtain the probability value using software is given below:

Open an EXCEL sheet.
In cell A1, enter “=NORM.S.DIST(0.5,1)”.
Click Enter.

The output obtained is shown below:

Fundamentals of Biostatistics, Chapter 5, Problem 1P

Thus, the probability, P(Z<0.5),is 0.6915.

Answer 14

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