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LMarieee Group Title

Some psychologists believe that a "genius" should be defined as anyone having an IQ over 140. If IQ scores are? normally distributed with a mean of 100 and a standard deviation of 17, and if the population of the world is 6,575,000,000, how many geniuses are there in the world today?

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  1. best.shakir Group Title
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    http://answers.yahoo.com/question/index?qid=20090509090635AAcZ2iP

    • one year ago
  2. best.shakir Group Title
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    mean = 100 SD = 15 z-value = (140 - 100)/15 = 2.67 to 2 DP looking up a z- table, P[IQ >140] = 0.0038 or 0.38% so estimated # of geniuses = 0.38% of 6,575,000,000 = 24,985,000 [C] <=== ANS

    • one year ago
  3. LMarieee Group Title
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    That was wrong, thank you tho.

    • one year ago
  4. UnkleRhaukus Group Title
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    • one year ago
  5. UnkleRhaukus Group Title
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    that's 0.93%

    • one year ago
  6. UnkleRhaukus Group Title
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    61,147,500

    • one year ago
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