Question is:
The average national SAT score is 1019. If we assume a bell-shaped distribution and a standard deviation of 110, what percentage of scores will fall above 799?
All I know is that it probably has something to do with z-scores and percentiles. I would appreciate your help!
The average national SAT score is 1019. If we assume a bell-shaped distribution and a standard deviation of 110, what percentage of scores will fall above 799?
All I know is that it probably has something to do with z-scores and percentiles. I would appreciate your help!
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1019-799 = 220, which is 2 standard deviations.
We know 95% of the population falls within 2 SD of the mean.
5% is outside of the 2 SD, 2.5% above and 2.5% below.
Only exclude the 2.5% below, and your answer is 97.5%
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We know 95% of the population falls within 2 SD of the mean.
5% is outside of the 2 SD, 2.5% above and 2.5% below.
Only exclude the 2.5% below, and your answer is 97.5%
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