Representations of linear functions
Changing grades
A math teacher graded student exams on
a scale of 0-100. After finishing, the teacher decided to
raise the grades. Students
could choose one of the following methods to have their grades raised:
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method 1
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method 2
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method 3
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Adding 10 points to the grade.
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Increasing the grade by %25.
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Adding to the grade half
the difference between
the grade and 100.
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The first method is
shown below in three representations:
a computing machine that calculates the updated
grade, a graph, and a value table.
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Using the Computing-machine
tool, construct computing machines to help
students compute their updated grades according to
methods 2 and 3. Use the
Representation of functions
tool to present graphs and value tables of functions that
describe the dependence of the updated grade on the original grade.
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Suggest a way to determine the best grade-correction method
for each student without having to compute their grades using all
three methods.
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What will be the range of grades after
the correction?
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Propose another method for raising the grades, which all students will prefer
over the existing methods.
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grade after change
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| grade before change
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