# 1990 mean number of lab classes for biology majors in

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Unformatted text preview: and AP are registered trademarks of the College Entrance Examination Board. 17 AP® STATISTICS 2002 SCORING GUIDELINES (Form B) Question 6 Solution Part (a): Part 1: States a correct pair of hypotheses, with symbols defined. µ1990 = mean number of lab classes for Biology majors in 1990 µ2000 = mean number of lab classes for Biology majors in 2000 H 0 : m1990 = m2000 H 0 : m1990 ¹ m2000 Part 2: H 0 : m1990 - m2000 = 0 H 0 : m1990 - m2000 ¹ 0 OR Identifies a correct test (by name or by formula) and checks (not just lists) appropriate assumptions. Two-sample t test t= x1990 - x2000 - 0 s 21990 s 2 2000 + n1 n2 = 1.83 - 1.93 1.292 1.37 2 + 200 200 Conditions: 1. Random samples – given in problem statement 2. Normal population distributions or large samples. Populations aren't normal, but since n1 = 200 and n2 = 200 are both large, it is OK to perform the t test. OR Student may select the two-sample z test, using z = x1990 - x2000 - 0 s 21990 s 2 2000 + n1 n2 as long as they comment on the large sample size. Copyright © 2002 by Colle...
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## This note was uploaded on 09/06/2013 for the course MATH AP Statist taught by Professor Mosby during the Spring '13 term at Silverton High School, Silverton.

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