Question

6. (12 pts, 2 pts each) The Graduate Record Exam (GRE) has a combined verbal and quantitative mean of 1000 and a standard deviation of 200. Scores range from 200 to 1600 and are approximately normally distributed. For each of the following problems: (a) Indicate the percentage or score called for by the problem. (b) Select the appropriate distribution curve (from below) that relates to the problem 1410 00 Curve C 100 60 1000 Curve 140 0 Curves Page 3 of 6

Answer 1

c Score Below what do the bottom 30.9% of the test takes Score. P(x2x)=0.309 z value for this probability is. z = 0.499 x - l 2 x = ZJ tu. C = -0.499x 200 t looo. 900.2 : x=900 Curve Round to closest integer. Curve type is Please 90a like.

Standard deviation (T) = 200 Mean (U)= 1000 a] Percentage of the rest score persons who take above 1400 P(x>1400) P (x-4 > 1400 - 1000 1009) = x - el zoo SNV - P(232) = 1- P(Z <2). - 1 - 0.9773 : Pex>1400) 0.0227 : Percentage 2.27 % Curve type is Curve B I LOO 6] test score above 700 P( x > Woo) 700-1000 P(x-> 27 -1.5) - P(Ze-1.5) 20 P(z 1-0.0668 P(x? > 700) 0.9332 Percentage - 93.32% is Curve Curve type 70.