Among the senior class at a high school, 55% of Ms. Keating’s students plan on majoring in a branch of STEM, while 49% of Ms. Lewis’s students plan on majoring in a branch of STEM. Suppose Ms. Keating chooses 25 of her students at random and Ms. Lewis chooses 23 of her students at random. Since nKpK, nK (1 – pK) and nLpL, nL (1 – pL) are all greater than 10, the Normal condition is met. Let K = the proportion of Ms. Keating’s students from the sample who plan on majoring in a branch of STEM, and let L = the proportion of Ms. Lewis’s students from the sample who plan on majoring in a branch of STEM. What is the probability that the proportion of students who plan on majoring in a branch of STEM is greater for Ms. Keating?
Find the z-table here.