Write the rule for the error produced in the result due to the addition and subtraction of physical quantities.

(N/A) When two physical quantities $A$ and $B$ having absolute errors $\Delta A$ and $\Delta B$ respectively are added or subtracted,the result is $Z = A \pm B$.
The absolute error in the result $Z$,denoted by $\Delta Z$,is given by the sum of the absolute errors of the individual quantities.
That is,$\Delta Z = \Delta A + \Delta B$.
This means that when two quantities are added or subtracted,the absolute errors in the individual quantities are added to get the absolute error in the final result.