Question

I am interested in determining which sex, male or female, is more likely to have a tattoo. I collected data from 240 females and 215 males. 100 of the females and 67 of the males reported having at least one tattoo. I fed the data into Statistix and the following printout was produced. Hypothesis Test Two Proportions Sample Size Successes 240 100 215 67 Sample 1 Sample 2 Difference Proportion 0.41667 0.31163 0.10504 Null Hypothesis: P1 = P2 Alternative Hyp: P1 P2 SE (difference) z (uncorrected) 0.04526 2.22 P 0.0262 95% Confidence Interval of Difference 0.01716 < P1-P2 < 0.19292 Which of the following assumptions are needed for this analysis to be valid? The populations of all females and males need to be both approximately normally distributed The population variances are equal. We need random and independent samples of females and males

Answer 1

The solution to this problem is given by

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