Question

Q1) Give the R code for the following problems. Only syntax is required.  

a) Suppose IQ is normally distributed with a mean of 100 and a standard deviation of 15. Give the R code needed to find the IQ that separates the top 5% from the others.

b) Suppose IQ is normally distributed with a mean of 100 and a standard deviation of 15. Give the R code needed to find the IQ that corresponds to the 75% percentile.

c) Suppose IQ is normally distributed with a mean of 100 and a standard deviation of 15. Give the R code needed to find the probability a randomly selected person has an IQ less than 80.

Answer 1

######### R-code:

mu=100
sig=15

#PART-a
IQ1= qnorm(1-0.05, mu ,sig)
IQ1

#PART-b
IQ2= qnorm(0.75, mu ,sig)
IQ2

#PART-c
prob= pnorm(80, mu ,sig)
prob