The length and breadth of a plate are  (10±0.1) cm and (6±0.2)cm respectively. The area of the plate is

A=lbΔAA=Δll+Δbb⇒ΔA=A(Δll+Δbb)                                       =60(0.110+0.26)                                      =60(0.6+260)=2.6                A±ΔA=(60±2.6)cm2