SOLUTION: Orders received by a particular firm have amounts that follow a normal distribution with a mean of RM103.60 and a standard deviation of RM8.75. (a) What percentage of orders wil

Algebra ->  Probability-and-statistics -> SOLUTION: Orders received by a particular firm have amounts that follow a normal distribution with a mean of RM103.60 and a standard deviation of RM8.75. (a) What percentage of orders wil      Log On


   

Question 1162958: Orders received by a particular firm have amounts that
follow a normal distribution with a mean of RM103.60 and
a standard deviation of RM8.75.
(a) What percentage of orders will have amount below
RM120.05?
(b) What percentage of orders will have amount over
RM92.75?
(c) What will be the amount such that approximately
25% of orders are for greater amounts?
(d) Above what amount will 90% of orders lie?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
mean is 103.6
standard deviation is 8.75

i used the online statistics calculator at https://homepage.divms.uiowa.edu/~mbognar/applets/normal.html

i confirmed the solutions are correct using the TI-84 Plus.

(a) What percentage of orders will have amount below
RM120.05?
my inputs were:
mean = 103.6
standard deviation = 8.75
x = 120.05
p(X < x) = .96995



(b) What percentage of orders will have amount over
RM92.75?
my inputs were:
mean = 103.6
standard deviation 8.75
x = 92.75
p(X > x) = .89251



(c) What will be the amount such that approximately
25% of orders are for greater amounts?
my inputs were:
mean = 103.6
standard deviation = 8.75
p(X > x) = .25
x = 109.50179



(d) Above what amount will 90% of orders lie?
my inputs were:
mean = 103.6
standard deviation = 8.75
p(X > x) = .90
x = 92.38642