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Unformatted text preview: these customers. You find that the average time to repair is 1.25 hours with a standard deviation of .75 hours . Should you order the copiers? 3. Exercise 7.3 on page 436 4. Exercise 7.7 on page 439 5. (7.76) Two sample t significance test and confidence interval: Does cocaine use by pregnant women cause their babies to have low birth weight? To study this question, birth weights of babies of women who tested positive for cocaine during a drug screening test were compared with the birth weights for women who either tested negative or were not tested, a group we call “other.” Here are the summary statistics. The birth weights are measured in grams: Group n x bar s Positive Test 134 2733 599 Other 597 4 3118 672 a) Formulate appropriate hypotheses and carry out the test of significance for these data? b) Give a 95% confidence interval for the mean difference in birth weights. 6. Exercise 7.78 on page 485 part a 7. Exercise 7.62 on page 481 8. Exercise 7.73 on page 483...
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This note was uploaded on 02/27/2008 for the course BCOR 1020 taught by Professor Liang,fang during the Summer '07 term at Colorado.
- Summer '07