Listed in the data table are IQ scores for a random sample ofsubjects with medium lead levels in their blood. Also listed arestatistics from a study done of IQ scores for a random sample ofsubjects with high lead levels. Assume that the two samples areindependent simple random samples selected from normallydistributed populations. Do not assume that the population standarddeviations are equal. Complete parts​ (a) and​ (b) below. Use a0.01 significance level for both parts. Medium Lead Level 72 94 9285 87 97 83 92 104 111 91 High Lead Level n2 = 11 x bar2 = 89.345s2 = 10.173
The test statistic is
nothing.
​(Round to two decimal places as​ needed.)The​ P-value is
nothing.
​(Round to three decimal places as​ needed.)
State the conclusion for the test.
A.
Fail to rejectFail to reject
the null hypothesis. There
is notis not
sufficient evidence to support the claim that subjects withmedium lead levels have higher IQ scores.
B.
RejectReject
the null hypothesis. There
isis
sufficient evidence to support the claim that subjects withmedium lead levels have higher IQ scores.
C.
Fail to rejectFail to reject
the null hypothesis. There
isis
sufficient evidence to support the claim that subjects withmedium lead levels have higher IQ scores.
D.
RejectReject
the null hypothesis. There
is notis not
sufficient evidence to support the claim that subjects withmedium lead levels have higher IQ scores.
b. Construct a confidence interval suitable for testing theclaim that the mean IQ scores for subjects with medium lead levelsis higher than the mean for subjects with high lead levels.
nothingless than​(Round to two decimal places as​ needed.)
Does the confidence interval support the conclusion of the​test?
â–¼
No,
Yes,
because the confidence interval contains
â–¼
zero.
only positive values.
only negative values.
Click to select your answer(s).
