Distance travelled in a week by sales staff employed by nationwide security firm is approximately normally distributed with a mean of 200 miles and standard deviation of 48 miles. Estimate the percentage of staff who in a week travel:

Question

1.
a)less than 80 miles
b)more than 250 miles
c)between 100 and 300 miles
2.A reduced mileage rate is to be introduced which is to be set such that approximately 20% of the sales staff will be affected? What is the maximum miles per week that a member of staff could travel before reaching the reduced mileage rate?
3)
Complete this sentence:
"80% of sales staff travel between ____ and ______ miles each week".

Answer 1

try this webpage, it's perfect for your question

http://davidmlane.com/hyperstat/z_table.html

Answer 2

Thanx but i need the questioned answered a.s.a.p