Posted by **Amy** on Wednesday, June 24, 2009 at 6:21pm.

Two problems:

1. Find D sub 3 of the following data set:

60, 40, 26, 33, 23, 53, 36, 23, 28, 12, 30, 47

2. Find P sub 26 of the following 25 scores:

38.5, 41.5, 52, 52.5, 61, 63, 63.5, 68, 69, 69, 78.5, 79, 80, 83, 87, 88.5, 88.5, 91, 91.5, 92, 92.5, 94, 94, 97, 97

I have a formula that says (X-mean)/standard deviation, but I'm not really sure if/how that helps here.

Help is greatly appreciated!

- Statistics -
**economyst**, Thursday, June 25, 2009 at 9:37am
What do you mean by "D sub 3"

Does "P sub 26" mean the projected value of the 26th observation? If so, and if the scores are in sequential order, you could run a linear regression to get the projected value.

X-mean/SD is the inverse of the "coefficient of variation". I cant see why this is relevant here.

- Statistics -
**Amy**, Thursday, June 25, 2009 at 8:06pm
It was Decile 3 and the 26th percentile. I worked it out with my teacher in class today.

I appreciate the effort though :)

## Answer this Question

## Related Questions

- math! - george entered a function into his calculator andfound the following ...
- check! - Write a recursive formula that generates the terms of the following...
- chemistry - I was way off on the other problem. But I see how you got the answer...
- half-life - If 250mg of a radioactive element decays to 200mg in 48 hours, find ...
- alg2 (sequences) - how do i find the pattern for: -4,8,-12,16 if the last number...
- Math (pre-calculus) - Hi! I have a question! I forgot how to do these two ...
- Statistics - Consider pairs <x,y>,...,<xn,yn> for i=1, ...,n. zi=cxi...
- Math - If there is a recursively defined sequence such that a1 = sqrt(2) an + 1...
- man alive! can someone check for me? - I am so bad when it comes to mathI I ...
- math - What are the following symbols used in math sequences: a sub i, n, N? ai ...