Wife had an exam today and she thinks she missed these questions.

who can make sense of them?

High school math

yes whats the answers? I admit i didnt bother to read em.

First one:

25 values, already ordered ascending, nearest rank method

P60, so 60/100*25 (no of values) = 15

The 15th value is your 60th percentile, 60% of values are below. The 15th value in the list is **26**.

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You’re a clever bloke. I had no idea about any of the answers. But then again, the last time I had to use such math was 38 years ago.

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1, 2, 4 seem OK to me. #3 I think she rounded 0.8095 incorrectly.

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Wait, so these 4 answers were already marked as wrong? Hmm, now I’m feeling even dumber than usual…

#3 (exam numbering) If they defined percentile as > and not >=, then it would be 28.

I’m very curious about #6 and 9.

Wouldn’t it be 27? So that 60% of the values are below (including 26) and 40% of the values are above (including 28).

As in, the median of [10,12] would be 11, not 10.

Question 6 & 9 I would have given the same answer. Maybe their rounding system is just effy. Or maybe…

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I’m drinking gin

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I feel you. Math makes my brain hurt.

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Yeah, might be!

Also figured out one thing: In the 2nd pic (question #6) the result is correct if you round the end result (what I would do). But if you round the probability for 0 and 1 first to 3 digits and then add them up the end result changes. Maybe that’s what they were going for.

I’m on Scotch. Math hurts me nearly as much as the numerous canings I got at school.

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You loved them really

Well, there was a stigma to it. Every time I got six of the best, there would be a crowd of fawning gawpers outside the headmaster’s office. watching me walk out with a smile on my face. And every new time, the prick tried to lash me harder. Broke a few canes in the process. But he never broke me.

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I think she said she missed one of these and got a B instead of an A or she missed these 4 and got a B

Something like that

Will have to ask her tomorrow

Off to snooze with me as it’s almost 1am here

Question 6 looks right.

Case 1: How many ways can you get zero correct answers? One way: they are all wrong. So (0.5)^6

Case 2: How many ways can you get one correct answer? Six ways. So 6*(0.5)^6.

So add these cases together, and the answer is 7*(0.5)^6 = 0.109375

(* means multiplication)

So she got all of the 4 wrong.