Question
Let a physical quantity X be measured in an experiment and the experiment be repeated for n times. If measured values are X1 X2......Xn then find the range in which all the measured values will lie.
Solution
When there are 'n' measured values, we cannot take any value as the true value.
Thus, true value is the mean of all the observed values.
The absolute error in measured values is,
Now the mean absolute error is ,
This means absolute error is the maximum possible error in the measurement.
Thus, all measured values of measurement lie in the range,
i.e.,