Question: From a population of 25,000 Americans in 1969; it was discovered that their collective IQ Score mean was 105 with a standard deviation of 12.
a. how many IQ scores exceeded 115?
b. what is the probability of IQ scores that fell between 68 and 75?
c. how many IQ scores fell above 3 standard deviations?
d. what is the percentage of IQ scores less than 125?
e. find where the worst 70% of IQ scores fall?
f. to be considered a "genius"; an IQ score must exceed 145; how many made it?
g. find a 90% confidence interval?
h. how many IQ scores fall below 1 standard deviation?
i. find where the worst 10% of IQ socres will fall?
j. find the best IQ score?