## DarkendSinz30 2 years ago A Math test has a mean of 39 and standard deviation of 18.0. Find the corresponding z scores for: I. a test score of 31 II. a test score of 100 Please show all of your work

1. sirm3d

the z score formula is $z=\frac{ obsv - mean }{ std.dev. }$ i'll leave the computation to you. post your answers here.

2. DarkendSinz30

what is obsv?

3. DarkendSinz30

z=31-39/18.0 correct?

4. DarkendSinz30

z=100-39/18.0 = 3.4

5. DarkendSinz30

z=31-39/18.0=.44

6. DarkendSinz30

is this right so far?

7. sirm3d

there is a negative sign

8. sirm3d

I. z = -0.44 II. z = 3.4

9. DarkendSinz30

okay so I was on the right track then just forgot the negative sign

10. sirm3d

just be careful with the signs.

11. DarkendSinz30

Thank you so much for the help.