Answer: Hello your question is poorly written attached below is the complete question
answer : 101.8
Step-by-step 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
