I want to apply to a university where the 25th /75th percentiles for the SAT Math are 490 / 620 respectively, but I am curious how would I find the mean and the standard deviation assuming that the data is normally distributed? I know that we are talking about the middle 50th-percentile and z_0.25=620 and z_0.75=490

princetonaqo3 2022-10-24 Answered
I want to apply to a university where the 25th /75th percentiles for the SAT Math are 490 / 620 respectively, but I am curious how would I find the mean and the standard deviation assuming that the data is normally distributed? I know that we are talking about the middle 50th-percentile and z 0.25 = 620 and z 0.75 = 490
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Answers (1)

Taxinov
Answered 2022-10-25 Author has 18 answers
If you want an EXCEL Solution, here it is:
The two equations are:
490 μ σ = Normsinv(.25) = -0.67449
620 μ σ = Normsinv(.75) = 0.67449
Solve for μ and σ
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