Can someone help me with this?

Question

Counting the length L and the width d of an oblong square we find the following numbers:

L: 24.25 / 24.26 / 24.22 / 24.28 / 24.24 / 24.25 / 24.22 / 24.26 / 24.23 / 24.24

d: 50.36 / 50.35 / 50.41 / 50.37 / 50.36 / 50.32 / 50.39 / 50.38 / 50.36 / 50.38

Measure the surface of the oblong square and the "mismeasure" with 2 ways:

a) From Li, di calculate δL and δd and S and δS.
b) From Li and di, calculate Si and then δS

Please help me with this, and I do not want just the answer, I want the whole solution as well so as to understand it.. Thanks in advance!

Answer 1

I'm not sure what you are looking for as I don't recognize your symbols.

I would start with the mean and the standard deviations of the two data sets:

the mean is just the average

the individual deviations are the differences between the values and the mean.

the standard deviation is:
sqrt((1/N) x (sum of the squares of the N deviations))

see:
http://en.wikipedia.org/wiki/Standard_deviation

The means are the best estimates of the length and width, and the standard deviations give you an idea of how close those estimates are.

For better estimates, you need to use the Student's t distribution:
http://en.wikipedia.org/wiki/Student%27s_t-distribution

but there is no point in getting into it until we know what it is you really need to compute.