In measuring the sides of a rectangle,one side is taken 5% in excess,and the other 4% in deficit.Find the error percent in the error percent in the area calculated from these measurements.  Options
A) 0.8 %	B) 0.2 %	C) 0.4 %	D) 0.9 %	E) 0.6 %

Rationale: "let x and y be the sides of the rectangle . then , correct area = xy . calculated area = ( 105 / 100 * x ) * ( 96 / 100 * y ) = 504 / 500 * xy . error in measurement = 504 / 500 * xy ) - xy = 4 / 500 * xy . error % = [ 4 / 500 * xy * 1 / xy * 100 ] % = 4 / 5 = 0.8 % . answer is a"
Answer: A