Question

On a planet far far away from Earth, IQ of the ruling species is normally distributed with a mean of 107 and a standard deviation of 18. Suppose one individual is randomly chosen. Let X = IQ of an individual.

a. What is the distribution of X? X ~ N(,)

b. Find the probability that a randomly selected person's IQ is over 116.  Round your answer to 4 decimal places.

c. A school offers special services for all children in the bottom 3% for IQ scores. What is the highest IQ score a child can have and still receive special services? Round your answer to 2 decimal places.

d. Find the Inter Quartile Range (IQR) for IQ scores. Round your answers to 2 decimal places.
Q1:  
Q3:  
IQR:  

Answer 1

a)

b)

P(X>116) =?

c)

A school offers special services for all children in the bottom 3% for IQ scores. What is the highest IQ score a child can have and still receive special services? Round your answer to 2 decimal places.

d)

IQR = Q3-Q1=119.14082-94.8591=24.2817