A researcher asked random samples of 50 kindergarten teachers and 50 12th grade teachers how much money they spent out-of-pocket on school supplies in the previous school year, To see if teachers at one grade level spent more than the other. A 95% confidence interval for ?_K ? ?₁₂ is $30 to $50. Based on this result, it is reasonable to conclude that A) 95% of all kindergarten teachers spend between $30 and $50 more than 95% of all 12th grade teachers. B) each kindergarten teacher spends $30 to $50 more than any 12th grade teacher. C) kindergarten teachers spend more on average than do 12th grade teachers. D) 12th grade teachers spend more on average than do kindergarten teachers.

Question

Quizplus · Accepted Answer

The confidence interval of $30 to $50 for the difference in means (?_K ? ?₁₂) suggests that, on average, kindergarten teachers spend more than 12th grade teachers.

A Researcher Asked Random Samples of 50 Kindergarten Teachers and 50