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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Naaaa really not. Don’t get why 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.
