SOLUTION: A teacher gives a final exam and the scores range from 40 to 80. The teacher decides to scale the exam in order to make the scores range from 60 to 90. Let x represent the origina
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-> SOLUTION: A teacher gives a final exam and the scores range from 40 to 80. The teacher decides to scale the exam in order to make the scores range from 60 to 90. Let x represent the origina
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Question 67290: A teacher gives a final exam and the scores range from 40 to 80. The teacher decides to scale the exam in order to make the scores range from 60 to 90. Let x represent the original score and let y represent a converted score.
Use the ordered pairs (40, 60) and (80, 90) to write the equation that the teacher will use to scale the exam scores.
You can put this solution on YOUR website! A teacher gives a final exam and the scores range from 40 to 80. The teacher decides to scale the exam in order to make the scores range from 60 to 90. Let x represent the original score and let y represent a converted score.
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Use the ordered pairs (40, 60) and (80, 90) to write the equation that the teacher will use to scale the exam scores.
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Subtract 40 from the old score, (all scores are above 40)
Old score range of 40, compressed into a range of 30.
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In equation form:
y = .75(x-40) + 60
y = .75x - 30 + 60
y = .75x + 30
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The graph should look like something like this:
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you can check the equation using the given ordered pairs
