An error 2% in excess is made while measuring the side of a square. The percentage of error in the calculated area of the square is:

Question:
An error 2% in excess is made while measuring the side of a square. The percentage of error in the calculated area of the square is:

[A].

2%

[B].

2.02%

[C].

4%

[D].

4.04%

Answer: Option D

Explanation:

100 cm is read as 102 cm.

A1 = (100 x 100) cm2 and A2 (102 x 102) cm2.

(A2 – A1) = [(102)2 – (100)2]

= (102 + 100) x (102 – 100)

= 404 cm2.

Percentage error =		404	x 100	%	= 4.04%
		100 x 100