Question

1. Scores on an IQ test for the 18-to-30 age group are approximately normally distributed with a mean of 110 and a standard deviation 25. Scores for the 31-to-40 age group are approximately normally distributed with mean 100 and standard deviation 20. Phoebe, who is 25, scores 130 on the test. Amandeep, who is 36, also takes the test and scores 116. Who scored higher relative to her age group, Phoebe or Amandeep?

a) Phoebe

b) Amandeep

c) They scored the same

d) It cannot be determined with the information given

2. A 99% confidence interval for a population mean is determined to have lower and upper limits of 32.7 and 42.8 respectively. If the confidence level is changed to 95%, then the sample mean

a) becomes smaller

b) becomes larger

c) does not change

d) changes based on the z critical value

e) cannot tell based on the given information

Answer 1