2005, Question 3 · 4 points
Train fuel use versus number of railcars
Use a scatterplot, residual plot and regression output to judge a linear model, turn the slope into a cost estimate per added railcar, interpret r squared, and judge extrapolating to 65 railcars.
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.
Lessons this question draws on
1 Read the question
The question is College Board's, from the 2005 exam. It starts on page 8 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 March 16, 2026.
2 Write your answer
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Scoring guidelines (PDF, page 7) What the exam readers saw (Student Performance Q&A)
Question, scoring guidelines and Chief Reader report: College Board, from the Internet Archive. The title, summary are ours.