DECILES the deciles of any distribution at the points tht mark off the lowest 10% and the highest 10%. The deciles of a density curve are therefore the points with are 0.1 and 0.9 to their left under the curve.

a) What are the declies of the standard Normal distribution?

b) The heights of young women are approximately Normal with mean 64.5 inches and standard deviation 2.5 inches. what are the declies of this distribution? show your work

Question

DECILES the deciles of any distribution at the points tht mark off the lowest 10% and the highest 10%. The deciles of a density curve are therefore the points with are 0.1 and 0.9 to their left under the curve.

a) What are the declies of the standard Normal distribution?

b) The heights of young women are approximately Normal  with mean 64.5 inches and standard deviation 2.5 inches. what are the declies of this distribution? show your work

amistre64 · Answer

decilies are every 10%

amistre64 · Answer

hmm .... and area of 1% under the curve eh

amistre64 · Answer

"therefore the points with are 0.1 and 0.9 to their left under the curve"  this part almost makes sense .... can you clarify it?

amistre64 · Answer

it looks like you want the zscore associated with 10%

amistre64 · Answer

your best bet, if you aint got a calculator that does the invNorm(%) is tho use the ztable in the back of a book

anonymous · Answer

i have a ti 84

amistre64 · Answer

thatll work :)

hit 2nd and vars to get the distribution menu

amistre64 · Answer

scroll down and you should see the "invNorm()" function

anonymous · Answer

what i do next?

amistre64 · Answer

type in (.1,mean,sd) ; since its a normal distribution the mean = 0 and the sd = 1

invnorm(.1,0,1)

amistre64 · Answer

then it should give you a number close to 1.282

anonymous · Answer

i got a negative

amistre64 · Answer

thats fine ...

anonymous · Answer

ok is the mean always 0

amistre64 · Answer

|dw:1315534791327:dw|

amistre64 · Answer

nope, the mean changes and so does the standard deviation (sd) as you can see in the next problem

amistre64 · Answer

unless stated, the mean is 0 and the sd is 1

amistre64 · Answer

the mean is the line i drew in the middle of the humpback; you have -zscores to the left and + zscores to the right

amistre64 · Answer

the zscore for 10% = what, -1.282 or so?

anonymous · Answer

i got that

amistre64 · Answer

the zscore for 90% then is just the postive of that

amistre64 · Answer

The heights of young women are approximately Normal  with mean 64.5 inches and standard deviation 2.5 inches. what are the declies of this distribution? show your work

now for this one its the same thing, but mean = 64.5 and sd = 2.5

amistre64 · Answer

invnorm(.1,64.5,2.5) = zscore

anonymous · Answer

is it 61?

amistre64 · Answer

close enough :)

amistre64 · Answer

now plug in .9 for the other one since we aint circling about a 0mean anymore

amistre64 · Answer

should give you about 68 for the 90%

anonymous · Answer

thank you teach better than my tracher

anonymous · Answer

teacher*

amistre64 · Answer

when i was going thru it during the summer term in college, my teacher was pretty much running thru it like it was on fire ...

anonymous · Answer

my teacher just shows us magic tricks instead of teaching the lesson

amistre64 · Answer

lol .... chris angel is teaching your class?