Question

STAT 10 Study guide for Test 2 1. Assume the random variable x is normally distributed with mean = 50 and standard deviations = 8.1. Compute the following probability. Be sure to draw a normal curve with the area corresponding to the probability shaded. Round your answers to two decimal places a. P(x > 48.5) b. P(45 <x<51) 2. There are two college entrance exams that are often taken by students, Exam 1 and Exam 2. The composite score on Exam 1 is approximately normally distributed with mean 215 and standard deviation 5. The composite score on Exam 2 is approximately normally distributed with mean 1029 and standard deviation 245. Suppose you scored 28 on Exam 1 and 1220 on Exam 2. Which exam did you score better on? Justify your reasoning using the normal model.

Answer 1

Answer: 1) Given that, M = 50,0=81 Q) P(x348.5) 48.5-50 8.1 =P[z>=0.19) :|- P(Z <0.19] =1-0.4247 [from z-table] -0.5753 51-50 8.1 6) P(45<x<51) 45-50 ,X-M Eplus 8.1 = P(-0.692720-12) = P(Z <0.12]- P(Z <-0.62) 20.5478 -0-2676 :(0.2802 Thank your