Suppose the scores on a trivia quiz are normally distributed with a mean of 80 and a standard deviation of 5.
Which group describes 16% of the population of trivia quiz scores?
scores below 70
scores below 75
scores above 83
scores above 90
16% of the population has z-scores from -infinity to -1
16% of the population will be 1 standard deviation (or more) below the mean.....this is a score of 75
So....this represents all the scores below 75
[ 16% will also have scores above 85....but this isn't a choice ]