Posted by Norvin on Friday, June 8, 2012 at 9:04pm.
Reading readiness of preschoolers from an impoverished neighborhood (=20) was measured using a standardized test. Nationally, the mean on thios test for preschoolers is 30.9, with SD = 2.08.
a. children below the 30th percentile (in the bottom 30%) are in need of special assistance prior to attending school. What raw score marks the cutoff score for these children?

Math  MathMate, Friday, June 8, 2012 at 9:52pm
You can look up a normal distribution table to find that the zscore for the lower 30 percentile is z=0.475.
Use
Score = μ+σz to get the raw score. Remember that the value of z is signed.