An IQ test has a mean of 97 and a standard deviation of 10. Which is more unusua
ID: 3252948 • Letter: A
Question
An IQ test has a mean of 97 and a standard deviation of 10. Which is more unusual, an or 107 or an IQ of 79? Select the correct choice below and, if necessary in the answer boxes to complete your choice. A. An IQ of 79 is more unusual because its corresponding z-score, is further from 0 than the corresponding z-score of for an IQ of 107. (Type integers or decimals rounded to two decimal places as needed.) B. An IQ of 107 is more unusual because its corresponding z-score, is further from 0 than the corresponding z-score of for an IQ or 79. (Type integers or decimals rounded to two decimal places as needed.) C. Both IQs are equally likely.Explanation / Answer
Ans: Mean=97,std dev=10
z score for IQ of 107
z=(107-97)/10=1
P(z<=1)=0.8413
z score for IQ of 79
z=(79-97)/10=-1.8
P(z<=-1.8)=0.0359
Hence,IQ of 79 is more unusual as its corresponding z score(-1.8) is farther from 0 than the corresponding z score of (1) for an IQ of 107.
Hence,Option A is correct.