Question

MEDAL AND FAN! (:
A set of data with a mean of 45 and a standard deviation of 8.3 is normally distributed. Find the value that is –2 standard deviations away from the mean.

Answer 1

z = (x - mu)/sigma

-2 = (x - 45)/8.3


solve for x

Answer 2

What would be the first step to solving for x?

Answer 3

multiplying both sides by 8.3

Answer 4

-2 = (x - 45)/8.3

-2*8.3 = x - 45

-16.6 = x - 45

Answer 5

so then its -16.6(x-45)?

Answer 6

close, look at what I wrote above

Answer 7

Ohhhhhh okay so its 28.4?

Answer 8

wait thats not an option for an answer

Answer 9

what are your options?

Answer 10

20.1, 78.9, 69.9, 48.0

Answer 11

hmm I'm getting 28.4 as well, so not sure why it's not showing up

Answer 12

did we do it wrong?

Answer 13

double check all the numbers to make sure they are correct (like the 45 or 8.3 or -2)

Answer 14

no we did it correctly

Answer 15

Oh wow I'm sorry instead of -2 it is +3, I dont know how I did that

Answer 16

that's ok, glad you checked

Answer 17

so you need to solve

3 = (x - 45)/8.3

Answer 18

Okay I got 69.9 (:

Answer 19

me too

Answer 20

Thanks (:

Answer 21

yw