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# Wrong = % Right (Posted on 2007-06-16) Difficulty: 2 of 5
I finished grading tests for two classes when I noticed something interesting about the worst scoring student for each.

In the first class a student who got 46 problems wrong got 46 percent right (to the nearest whole percent.)
How many problems were there on this test?

In the second class there were 35 problems but again the lowest scoring student got the same number wrong as percent right (again rounded.)
How many questions did this student get wrong?

What is the smallest number of questions for which this kind of thing can happen?
(Aside from the trivial one question test.)

What if the percent must be exact instead of rounded?

[Note: This actually happened.]

  Submitted by Jer    
Rating: 3.5000 (2 votes)
Solution: (Hide)
With 85 questions, 46 wrong is 46% right

With 35 questions 26 wrong is 26% right

The smallest is with 15 questions where 13 wrong is 13% right

The smallest exact is with 25 questions where 20 wrong is exactly 20% right.

Comments: ( You must be logged in to post comments.)
  Subject Author Date
SolutionSolution To The Third Part : Exact CaseK Sengupta2007-06-17 05:27:04
SolutionSolution To The Third Part : Approximate CaseK Sengupta2007-06-17 05:24:40
SolutionSolution To The First Two PartsK Sengupta2007-06-17 05:21:56
SolutionSpoiler - Ans. to first 2 questionsKenny M2007-06-16 23:28:28
Some ThoughtsNo asides neededSteve Herman2007-06-16 16:46:46
Solutiona spoilerAdy TZIDON2007-06-16 13:58:31
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