2006, Question 6 · 4 points · about 25 minutes
Testing whether thermostat readings got less consistent
State hypotheses about a variance, compute and use a chi-square statistic to test them, mark the rejection region, and use simulated histograms to rank three populations by variance.
This exam had six free-response questions, each scored from 0 to 4. Its Question 6, the Investigative Task, is no longer part of the exam. The current exam has 4 free-response questions in 90 minutes. The skills these questions practice still count.
Not in the current course. Parts (b) to (f) use a chi-square test for a population variance, which the current course does not include.
1 Read the question
The question is College Board's, from the 2006 exam. It starts on page 10 of the PDF. College Board no longer posts this exam, so it opens from the copy of College Board's PDF that the Internet Archive saved on April 16, 2025.
Open Question 6 (PDF, page 10)
2 Write your answer
Answer each part the way you would on the exam, in full sentences, with your work shown. Your writing saves as you type.
3 Score it
Score your answer against College Board's scoring guidelines, one point at a time. Give yourself a point only when your answer says what the guideline asks for.
Scoring guidelines (PDF, page 19) What the exam readers saw (Student Performance Q&A)
Question, scoring guidelines and Chief Reader report: College Board, from the Internet Archive. The title and summary are ours.