Teens with phones Pew Research reported that, in 2013, 78% of all teens had a cell phone. Assume this estimate is correct. a) We randomly pick 100 teens. Let pn represent the proportion of teens in this sample who own a cell phone. Whats the appropriate model for the distribution of pn? Specify the name of the distribution, the mean, and the standard deviation. Be sure to verify that the conditions are met. b) Whats the approximate probability that less than three fourths of this sample own a cell phone?

Inference for two independent groups: - This means deciding if there’s a statistically significant relationship between explanatory and response variable - If response variable is quantitative, the question involves means o Ex. How does average childhood weight compare between generations - If the response variable is categorical, the question involves proportions o Ex. Does the smoking rate differ between genders Summary of inference for 2 independent population means: - Hypotheses: H 0μ 1μ =2 H A μ1−μ 2¿0 - Sample Statistic: ´ ´ X 1X 2