A paper summarizes data from 61 young children living in a particular county in a particular state who had
their blood lead levels measured as part of a routine healthcare visit. The sample mean blood level was
16 µg/dL and the sample standard deviation was 7.3 µg/dL. Suppose that it is reasonable to regard this
sample as representative of young children living in this county. Do these data provide convincing evidence
that the mean blood lead level for young children in this county is greater than 11 µg/dL? Carry out a
hypothesis test using
State the appropriate null and alternative hypotheses (in µg/dL). (Enter != for ≠ as needed.)
Find the test statistic. (Round your answer to two decimal places.)
Use technology to find the P-value. (Round your answer to four decimal places.)
Guide On Rating System
Vote
Null Hypothesis: The mean blood lead level for young children in this county is less than or equal to 11 µg/dL.
Alternative Hypothesis: The mean blood lead level for young children in this county is greater than 11 µg/dL.
Test statistic:
t = (sample mean - hypothesized mean) / (sample standard deviation / sqrt(sample size))
= (16 - 11) / (7.3 / sqrt(61))
= 1.56 (rounded to two decimal places)
Using technology to find the P-value, we can compare the test statistic to the t-distribution with degrees of freedom n-1 = 60. Assuming a significance level of 0.05, the P-value is 0.0632.
Got a question with my answer?
Cheapmath.com is completely free!
Asking question is free.
Getting answers is free.
+99