Concept explainers
a.
What was the average score on the original exam
a.

Answer to Problem 109E
The average score on the original exam was 80.
Explanation of Solution
Given:
Students in a mathematical class were given an exam and then tested monthly with an equivalent exam. The average scores for the class are given by human memory model
Calculation:
To find the average score on original exam, we will substitute
Therefore, the average score on the original exam was 80.
Upon graphing our given function, we will get:
We can see that at
b.
What was the average score after 2 months?
b.

Answer to Problem 109E
The average score after 2 months was 71.89.
Explanation of Solution
Given:
Students in a mathematical class were given an exam and then tested monthly with an equivalent exam. The average scores for the class are given by human memory model
Calculation:
To find the average score after 2 months, we will substitute
Therefore, the average score after 2 months was approximately 71.89.
Upon graphing our given function, we will get:
We can see that at
c.
What was the average score after 11 months?
c.

Answer to Problem 109E
The average score after 11 months was 61.65.
Explanation of Solution
Given:
Students in a mathematical class were given an exam and then tested monthly with an equivalent exam. The average scores for the class are given by human memory model
Calculation:
To find the average score after 11 months, we will substitute
Therefore, the average score after 11 months was approximately 61.65.
Upon graphing our given function, we will get:
We can see that at
Chapter 3 Solutions
PRECALCULUS W/LIMITS:GRAPH.APPROACH(HS)
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