you can get an idea of how these things work here:
http://davidmlane.com/hyperstat/z_table.html
try using your numbers, and you will see shaded areas.
I do not understand this homework at all. Any help or elaboration would be greatly appreciated. Thanks.
100 juniors at Southwest High took the SAT test. The scores were distributed normally with a mean of 22 and a standard deviation of 3. Label the mean and three standard deviations from the mean.
a) What percentage of scores are between 22 and 25?
b) What percentage of scores are between scores 16 and 28?
c) What percentage of scores is less than a score of 13?
d) What percentage of scores is greater than 25?
e) Approximately how many juniors scored higher than 22?
f) Approximately how many juniors scored between 19 and 25?
1 answer