Low Blood Lead Level: High Blood Lead Level: n = 78, x = 92.88462, s = 15.34451 n = 21, 3 = 86.90476, s = 8.988352
In Exercises 5–20, assume that the two samples are independent simple random samples selected from
IQ and Lead Exposure Data Set 7 “IQ and Lead” in Appendix B lists full IQ scores for a random sample of subjects with low lead levels in their blood and another random sample of subjects with high lead levels in their blood. The statistics are summarized below.
a. Use a 0.05 significance level to test the claim that the
b. Construct a confidence interval appropriate for the hypothesis test in part (a).
c. Does exposure to lead appear to have an effect on IQ scores?
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High Blood Lead Level:
n = 78, x = 92.88462, s = 15.34451
n = 21, 3 = 86.90476, s = 8.988352"
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