Question

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

Answer 1

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