In order to be invited to tutoring or extension activities, a student's performance must be at least 20 points higher or lower than an average score. if the average score is 105, which inequality represents p, the scores for students who are eligible for tutoring or extension activities?

D.  p ≤ 85 or p ≥ 125

You only have to meet 1 requirement, which A & B have 2.  

Due to the wording, at least 20 points, I would take that as meaning 105-20=85 is allowed or 105+20=125 is allowed.  

C, does not allow you to use 85,125.

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify