Question

From a nationwide study, we know that the mean diastolic blood pressure is 62.3 mm gH for children aged 5-6 years of age, and that the measurements are normally distributed. Blood pressure measurements were taken on 13 children aged 5-6 years living in a specific community to determine whether their living conditions resulted in a difference in mean blood pressure. For these children the average diastolic blood pressure was found to be 56.4 mm Hq with standard deviation 7.8 mm Hq a) The null hypothesis for this test will be: H0: < 56.4 H0: 56.4 H0: 62.3 H0: = 62.3 b) The alternative hypothesis for this test will be: Ha <56.4 Ha 56.4 Ha 62.3 Ha < 62.3 c) Compute the value of the test statistic. (Give answer to two places past decimal.) d) Find bounds on the P value for the test P < .01 .01 < P .05 .05 P.1 P .1 e) Is the evidence against H0 strong enough to reject at a = 0.05? Yes, reject H0 No, do not reject H0 Not enough information to decide.

Answer 1

a)

H0: $\mu$ = 62.3

b)

Ha: $\mu$ $\neq$ 62.3

c)

Test statistics

t = ($\bar{x}$ - $\mu$ ) / (S / sqrt(n) )

= (56.4 - 62.3) / (7.8 / sqrt(13) )

= -2.73

d)

From T table

With test statistics 2.73 and df of 12 ,

p-value(two tailed) is between , 0.01 < p < 0.05

e)

Since p-value < 0.05

Yes, reject H0