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
Look for z - score corresponding to .1600 ( or approximately I find - .99 )
How many Standard Deviations is this ? (.99) multiply the S.D. * 5 and subtract from 80 to find the score ... can you finish...?