Should I add uncertainties?

Should I add uncertainties? 

For example I have the uncertainty in the apparatus of +- 0.1 and the random uncertainty on the set of data (5 tries) is 0.2

I calculated the random uncertainty by doing the Max value-Min value divided by the Number of values. which is standard but should I quote the total uncertainty by 0.3? 

I need the answer very fast please for assignment