A sample of 21 Mensa members have had their Intelligence Quotients (IQs) measure
ID: 3172113 • Letter: A
Question
A sample of 21 Mensa members have had their Intelligence Quotients (IQs) measured and recorded. The data were used to calculate a 91% confidence interval for the mean IQ of all Mensa members. The confidence interval was calculated as 138 plusminus 11. According to this confidence interval, it is most reasonable to conclude that: there is a 91% chance that the mean IQ of all Mensa members is between 127 and 149 91% of all Mensa members have an IQ between 127 and 149 you are 91% confident the interval between 127 and 149 contains the mean IQ of all Mensa members the mean IQ of all Mensa members is between 127 and 149Explanation / Answer
91% of the time, when we calculate a confidence interval in this way, the true mean will be between the two values. 9% of the time, it will not. Because the true mean (population mean) is an unknown value,
We are 91% confident that the mean I.Q. is between 127and 149.”
optionC is correct.