In part c the student earned both points the first

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: t (b) because the meaning given does not address the time interval over which the average was computed. In part (c) the student earned both points. The first point was earned for correctly providing the definite integral that represents the number of hundreds of entries processed between 8 P.M. and midnight. The second point was earned for subtracting that value from the initial condition of 23 hundred entries in the box at 8 P.M. to obtain the answer. In part (d) the student earned the first point for setting P′( t ) = 0. The student does not consider the endpoints as candidates, so no additional points were earned. © 2010 The College Board. Visit the College Board on the Web: AP® CALCULUS BC 2010 SCORING COMMENTARY Question 2 (continued) Sample: 2C Score: 3 The student earned 3 points: 1 point in part (a), no points in part (b), 2 points in part (c), and no points in part (d). In part (a) the student sets up a correct difference quotient based on the values in the table and correctly evaluates for the numerical answer. In part (b) the student subtracts the function values at endpoints of the subintervals rather than adding them. The student interprets the integral expression as an average rate rather than an average number. In part (c) the student’s work is correct. “700” was accepted because of the units in this question. In part (d) the student never considers P′( t ) , so no points were earned. © 2010 The College Board. Visit the College Board on the Web:
View Full Document

This note was uploaded on 08/22/2013 for the course CALCULUS AP taught by Professor Staff during the Fall '11 term at Lakota West High School.

Ask a homework question - tutors are online