In measuring the sides of a rectangle, one side is taken 9% in excess, and the other 8% in deficit. Find the error percent in the area calculated from these measurements. Choices:	A) 0.11 %	B) 0.7 %	C) 0.4 %	D) 0.6 %	E) 0.28 %

Rationale: "let x and y be the sides of the rectangle . then , correct area = xy . calculated area = ( 12 / 11 ) x ( 23 / 25 ) y = ( 358 / 357 ) ( xy ) error in measurement = ( 358 / 357 ) xy - xy = ( 1 / 357 ) xy error percentage = [ ( 1 / 357 ) xy ( 1 / xy ) 100 ] % = ( 7 / 25 ) % = 0.28 % . answer is e ."
Answer: E