I know that The more systematic errors > the less accurate The more random errors > the less precise
So lets say we have a stopwatch which has a zero error -1 (every reading less then 1 the actual value)
and an old man is supposed to measure 60s
His readings are 65 ,50,54,62 mean value = 65+50+54+62/4 = 57.75
lets say we remove the systematic error(by adding 1 to each) and the readings become 66 ,51 ,55,63 mean value = 58.75
Although Now mean is more closer to the true value but why is not mean = 60 what am i getting wrong?