# Homework Help: What does it mean to determine the precision, expressed as percent

1. Nov 6, 2007

### gcatal

In my lab class, I needed to find k for a spring in two ways (hanging a mass from a spring & through simple harmonic motion). I've done this and now need to compare the two values - the question asks me to determine "the precision, expressed as a percent" of my measurements for k - I don't understand what this means.

Can someone advise me as to how I can go about determining the precision of a given value & expressing it as a %? Thank you.

Last edited: Nov 6, 2007
2. Nov 6, 2007

### learningphysics

I think they mean percentage error maybe... one way of doing it is taking +/- 1 of the last digit.

so 125g has a percentage error of [1g/(125g)]*100% = 0.8%

but don't know if this is how you're expected to do it.

3. Nov 7, 2007

### gcatal

I don't think that's it because they ask me for the percentage error later....they want the "claimed precision expressed as a percent". Thanks anyway.

4. Nov 7, 2007

### Feldoh

Precision is the amount of reproducibility I think, how easy it is to reproduce a particular result. So how close were K values maybe?