Among 157 African-American men, the mean systolic blood pressure was 146 mm Hg with a standard deviation of 27. We wish to know if on the basis of these data, we may conclude that the mean systolic blood pressure for a population of African-American is greater than 140. Use α=0.01. Solution 1. Data: Variable is systolic blood pressure, n=157, sample mean =146,s=27,α=0.01.

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Among 157 African-American men, the mean systolic blood pressure was 146 mm Hg with a standard deviation of 27. We wish to know if on the basis of these data, we may conclude that the mean systolic blood pressure for a population of African-American is greater than 140. Use α=0.01.  Solution 1. Data: Variable is systolic blood pressure, n=157, sample mean =146,s=27,α=0.01.

William Yazzie · Accepted Answer

Step 1  From the given information,  Sample size n=157  the Sample mean, x―=146mmHg  the Sample standard deviation, s=27mmHg  The appropriate null and alternative hypotheses are given below:  Here, μ is the true mean systolic blood pressure.  Null hypothesis, H0:μ=140  Alternative hypothesis, H1:μ&amp;gt;140  The population standard deviation is unknown. the appropriate test is one sample t test.  Degrees of freedom: 156(=157−1).  Step 2  Computation of test statistic value:  The formula for one sample t test is given below.  t=x―−μsn  Test statistic:  t=146−14027157  =2.78  The test statistic for the hypothesis test is 2.78.  p-value:  Using Excel function: “=TDIST(2.78,156,1)”, the p-value for the one-tailed test is 0.0031.  Here, the level of significance is 0.01.  Since the p-value is less than the level of significance 0.01, the null hypothesis is rejected.  At 0.01 significance level, there is sufficient evidence to conclude the mean systolic blood pressure for a population of African-American is greater than 140.

Among 157 African-American men, the mean systolic blood pressure was 1

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