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2.4 Exercise 10

Avg difficulty 2.5

A standardized test is given to ten people at the beginning of the school year with the results given in the table below. At the end of the year the same people were again tested.

  1. What is the average improvement?
  2. Does it matter if the means are subtracted, or if the individual values are subtracted?
Student Beginning score Ending score
1 1100 1120
2 980 1030
3 1200 1208
4 998 1000
5 893 948
6 1015 1030
7 1217 1224
8 1232 1245
9 967 988
10 988 997

OpenStax Introductory Business Statistics 2e, 2.4 Sigma Notation and Calculating the Arithmetic Mean, exercise 10

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Adapted from Introductory Business Statistics 2e © 2023 Rice University. Licensed under CC BY 4.0. Source: Introductory Business Statistics 2e. Imported at revision 50ec917.