Question

Sherry missed the lesson on normal distribution and needs to do her homework. Explain to Sherry how to use the mean and standard deviation of a normal distribution to determine the top 7% of the population.

Answer 1

@delila4675

Answer 2

okay here!!!

Answer 3

yup!

Answer 4

how do I find the mean and standard deviation of 7%?

Answer 5

ok first of all do u know what standard deviation means?

Answer 6

when reading questions all ways look for the key words that stand out.

Answer 7

so do know what standard deviation means?

Answer 8

uhh not really but isn't it the amount that doesn't really match the rest of the data?

Answer 9

okay here is the definition In statistics, the standard deviation (SD) (represented by the Greek letter sigma, σ) is a measure that is used to quantify the amount of variation or dispersion of a set of data values.

Answer 10

okay

Answer 11

now ok The question says Sherry missed the lesson on normal distribution and needs to do her homework. Explain to Sherry how to use the mean and standard deviation of a normal distribution to determine the top 7% of the population. We want
Φ(x−μσ)=1−0.07=0.93

Answer 12

thats the standard deviation equation?

Answer 13

We'd solve for x. Where as μ is the man, and σ is standard deviation.

Answer 14

Actually "determine the top 7% of the population" is sort of vague. I interpreted it to mean the score at which you would be at the border. The question is not very precise.

Answer 15

ok do you want to move onto the next one?

Answer 16

wait no not done.

Answer 17

First, you use
z=x−μσ
to find the z score. μ is mean and σ is standard deviation.
Next, you would look up z in your z table.
P=Φ(z)
In this case P is what you find in the table, and it is the probability that your score is under x.

Answer 18

With the current question, we have P is already provided. When looking at the top 7%, this is the opposite of being in the bottom 93%. So we let P=0.93.

We do the z table look up, but instead of looking up z, we find look to see what z value will give us 0.93.

Answer 19

then we can finally solve for x.

Answer 20

1.5 i think

Answer 21

How, try to find a z that will result you in getting 0.97

Answer 22

I mean 0.9300

Answer 23

have caulator. and brb.

Answer 24

ok im so lost

Answer 25

okay. here http://openstudy.com/study#/updates/5301ad54e4b024fe26e22d29

Answer 26

that might help.

Answer 27

brb have to eat but I will be back for next question ok?

Answer 28

by.

Answer 29

ok i will tag you in the next one.