Question

The number of music CDs sold weekly by a store follows a normal distribution with a mean of 455 and a standard deviation of 65. Which sentence summarizes this information?

A.There is an 84% chance that the shop sells more than 390 CDs in a week.
B.There is a 34% chance that the shop sells more than 390 CDs in a week.
C.There is a 34% chance that the shop sells fewer than 390 CDs in a week.
D.There is a 68% chance that the shop sells fewer than 390 CDs in a week.
E.There is a 95% chance that the shop sells more than 390 CDs in a week

Answer 1

please help

Answer 2

i just responded to the other post ....

Answer 3

you are most likely trying to relate this to the empirical rule; so define the z score associated with 390 given that the mean is 455 and the sd is 65

Answer 4

you said (390-455)/65?

Answer 5

since 390 is less then 490; the answer cannot possibly be less than 50

Answer 6

yes\[z=\frac{x-mean}{sd}\]

Answer 7

so B and C cannot be the answer

Answer 8

i got 383..

Answer 9

- 455
390
------
- 65

-65/67 = -1

Answer 10

...these fat fingers of mine ....

Answer 11

im so confused now lol

Answer 12

this is exactly the other question .. we want 50 + 68/2 by the same concepts

Answer 13

i think i misread some of the question tho

Answer 14

idk am i suppose to add or subtract

Answer 15

50 - 68/2 is better i was reading one little bit of information off

Answer 16

so -9? lol