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SAT math scores have a bell-shaped distribution with a mean of 515 and a standard deviation of 114.

What percentage of SAT scores is between 173 and 401?

Find the SAT Math score range that falls with 2 standard deviations.

Please explain!

1 Answer

12 votes

Hey there mate :)

Analysis :


401 = 515 - 114 = u - 6

And


173 = 515 - 3.114 = u - 36


= (p(u - 36 < u < u + 36) - p(u - 6 < u < u + 6))/(2)


= (99.73percent - 68.21percent)/(2)


= (31.46percent)/(2)


= {15.73percent}

Then, calculating,


u - 26 = 515 - 2 * 114 = 287

And


u + 26 = 515 + 2 * 114 = 743

Then,


The \: Range = (287,743)

Final Answers :-

15.73 %

(287,743)

~Benjemin360

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