i am having a dispute with my co worker over a calculation. we are dividing two numbers to get an area retention time and recording to 3 sig figs. we must do this 5 times. then we take the average of the 5 numbers and record to 3 sig figs(adsbygoogle = window.adsbygoogle || []).push({});

i am arguing that we must use the entire number which is 7 or 8 digits long when we calculate the average. she is saying we can just add up the 5 area retention times and take the average of them. i do not agree with the because we are only recording the 7 or 8 digit answer to 3 sig figs as it is. to take the average of 5 numbers that are only recorded to 3 sig figs doesn't sound precise to me.

this leads to another problem. we are then taking the result which would be our average area retention time and using it in another calculation. the calculation involves multiplying a 4 digit sig fig number by our 3 digit sig fig average retention time.

does anyone agree with me that there are several problems with my co workers thoughts on this?

anyones input would be wonderful.

also any documents, reports, or just anything you can think of that gives details of using averages in calculations would be greatly appreciated.

i have been looking on the internet for over 3 hours now trying to find something that says you should not use an average in a multiplication calculation when you are trying to give an accurate result.

i would just love to stick it to this old cow who has caused me loads of problems

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Have a question

**Physics Forums | Science Articles, Homework Help, Discussion**