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Suppose that IQ scores in one region are normally distributed with a standard deviation of . Suppose also that exactly of the individuals from this region have IQ scores of greater than (and that do not). What is the mean IQ score for this region

User Jnfr
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Answer: Hello your question is poorly written attached below is the complete question

answer : 101.8

Explanation:

Given data :

Standard deviation ( б ) = 14

55% have IQ scores > 100

45% have IQ scores < 100

Determine the mean IQ score for the region

P ( X > x ) =

P ( Z ≥ ( 100 - μ ) / 14 ) = 0.55 also

P ( Z ≤ ( 100 - μ ) / 14 ) = 0.45

using standard normal calculator

100 - μ / 14 = Z₀.₄₅ = - 0.126

resolving the relation above

100 - μ / 14 = - 0.126

μ = 100 - 14 ( -0.126 )

= 101.764 ≈ 101.8

Suppose that IQ scores in one region are normally distributed with a standard deviation-example-1
User Brockoli
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