Question

A person must score in the upper 2% of the population on an iq test to qualify for membership in mensa, the international high-iq society (us airways attache, september 2000). there are 110,000 mensa members in 100 countries throughout the world (mensa international website, january 8, 2013). if iq scores are normally distributed with a mean of 100 and a standard deviation of 15, what score must a person have to qualify for mensa (to the nearest whole number)?

Answer 1

135 Using a standard normal table, you can look up the number of standard deviations for the 98% value which will be 2.054. Then multiply this number by the standard deviations and add that to the mean to get the desired value. So 2.054 * 15 + 100 = 130.81 Rounding to the nearest whole number gives you 131.