The mean systolic blood pressure of adult males is normally distributed with a mean of 138 (millimeters of mercury) and a standard deviation of 9.7. What percent of adult males have blood pressure between 161.28 and

164.9?

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Just enter the data as you have it and choose the "between" option

http://davidmlane.com/hyperstat/z_table.html

To find the percentage of adult males with blood pressure between 161.28 and 164.9, we will use the normal distribution.

Step 1: Standardize the values
To use the normal distribution table, we need to convert the given blood pressure values into standard scores or z-scores. The formula for standardizing a value is:
z = (x - μ) / σ
where:
z is the z-score,
x is the given value,
μ is the mean, and
σ is the standard deviation.

For the lower value, 161.28:
z₁ = (161.28 - 138) / 9.7

For the upper value, 164.9:
z₂ = (164.9 - 138) / 9.7

Step 2: Find the corresponding area in the standard normal distribution table
Once we have the z-scores, we can find the area under the normal curve between those z-scores. The area represents the percentage of individuals with blood pressure within that range.

Look up the z-scores in the standard normal distribution table to find the corresponding areas.

Step 3: Calculate the percentage between the values
The percentage can be calculated by subtracting the area corresponding to the lower value from the area corresponding to the upper value.

Percentage = Area(z₂) - Area(z₁)

Using the standard normal distribution table or a calculator with a normal distribution function, find the areas corresponding to z₁ and z₂. Subtract the smaller area from the larger area to calculate the percentage.