AN IQ EXAM HAS A MEAN OF 200 AND A STANDARD DEVIATION OF 50. WHAT SCORE REPRESENTS THE 75TH PERCENTILE. IN THIS CASE WE KNOW THE MEAN, THE STANDARD DEVIATION BUT WE HAVE TO FIGURE OUT THE Z SCORE IN ORDER TO PLUG IT INTO OUR FORMULA TO FIND THAT SCORE WHICH REPRESENTS THE 75TH PERCENTILE.
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To find the z-score for the 75th percentile, we can use a standard normal distribution table or a calculator. The z-score for the 75th percentile is approximately 0.675. Show more…
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