Please explain 4 The scores on a college aptitude test foll

Please explain :)

4. The scores on a college aptitude test follow N(490, 70). Use Zscores and the 689599.7 Rule to
answer the following questions.
a) What percentage of scores will be between 350 and 560?
b) What percentage of scores will be above 420?
c) Suppose 4,000 college applicants took this aptitude test. Approximately how many of these
4,000 applicants would you expect to have scores of 700 and above?
d) Suppose that a certain college only accepts students who score in the top 2.5% on this test.
What score would a student need to obtain in order to be accepted to this college?

Solution