If L = 20.04 m `pm`0.01 m , B= 2.52 m `pm ` 0.02 m . What are the values of `(L xx B) and (L+B)` ?

Explanation

Given errors are absolute erros , while the rule says that percentage erros are to added, Hence , the first step will be to convert errors into percentage errors.
L = 20.04 m `pm (0.01)/(20.04) xx 100% =20.04 m pm 0.05%`
`B = 2.52 m pm (0.02)/(2.52) xx100 = 2.52 m pm 0.79%`
`L xx B =(20.04xx2.52) m^2 pm (0.05 + 0.79)% = 50.50 m^2 pm 0.84 %`
This is the result . However , since the data given in the question was in terms of absolute errors , so we should give our result also in absolute errors.
`L xx B = 50.50 m^2 pm (0.84)/(100) xx50.50 m^2 = 50.50 m^2 pm 0.42 m^2`