The length and breadth of a rectangular object are 25.2 cm and 16.8 cm respectively and have been measured to an accuracy of 0.1 cm. Find the relative error and percentage error in the area of the object.

Explanation

Area `A = l xx b`
`l = 5.2 cm and Delta l= 0.1cm`
`b = 16.8 cm and Deltab = 0.1 cm`
`:.` Relative error in area `((DeltaA)/(A)) = ((Delta l)/(l)) + ((Delta b)/(b))`
`= ((0.1)/(25.2)) + ((0.1)/(16.8)) = 0.004 + 0.006 = 0.01`
`((Delta A)/(A)) 100 = 0.01 xx 100`
Percentage error = 1%.