Question

One with a systolic blood pressure greater than 129 is considered to have high blood pressure. A study recorded the systolic blood pressures of 14 randomly selected Americans, which yielded a mean of 131.57 with standard deviation 15.88. Conduct a hypothesis test to see if you can say that Americans, on average, have high blood pressure.

1.Write the hypotheses for this test.

2.What is the test statistic?

3.What is the p-value?

4.Using α = 0.05, decide whether or not to reject the null hypothesis.

5.Based on your decision, is there evidence that Americans, on average, have high blood pressure?

Answer 1

Solution :

= 129

=131.57

S =15.88

n = 14

1 )This is the right tailed test .

The null and alternative hypothesis is ,

H0 :    = 129

Ha : >129

2 )Test statistic = t

= ( - ) / S / n

= (131.57-129) / 15.88 / 14

= 0.605

Test statistic = t = 0.605

3 ) P-value =0.2776

4 ) = 0.05  

P-value >

0.2776 > 0.05

Fail to reject the null hypothesis .

5 ) There is not sufficient evidence that Americans, on average, have high blood pressure.