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 original

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Question 67291: 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.

What will the original score of 45 become? Round the answer to the nearest whole number.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The original grades have a range of 80-40=40
The converted range is 90-60=30
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to convert the range of 40 to one of 30
mltiply as follows: (30/40)(40)=3/4(40)=0.75(40)=30
So the conversion factor is 0.75
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But the least score must be 60
So the equation is new score= (0.75)(old score) + 60
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To convert a score of 45 proceed as follows:
new score = 0.75(45) + 60
new score = 33.75 + 60 = 93.75
Rounded the new score = 94
Cheers,
Stan H.