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 # Wrong = % Right (Posted on 2007-06-16)
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.

 Subject Author Date Solution To The Third Part : Exact Case K Sengupta 2007-06-17 05:27:04 Solution To The Third Part : Approximate Case K Sengupta 2007-06-17 05:24:40 Solution To The First Two Parts K Sengupta 2007-06-17 05:21:56 Spoiler - Ans. to first 2 questions Kenny M 2007-06-16 23:28:28 No asides needed Steve Herman 2007-06-16 16:46:46 a spoiler Ady TZIDON 2007-06-16 13:58:31

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