I sold two watches for Rs. 300 each, one at loss of 20% and other at the profit of 20%. What is the percentage of loss (-) or profit (+) that resulted from the transaction?

A. (+)4

B. (-)1

C. (+)1

D. (-)4

Answer: Option D

Solution(By Examveda Team)

In such cases, always loss occurs. It can be calculated by this formula,
$$ = \frac{{{{\left( {{\text{loss or gain percentage}}} \right)}^2}}}{{100}} = 4$$
That is 4% of loss

Graphic Change method
100 == 20%(loss) ⇒ 120 == 20%(gain) ⇒ 96
% Loss = 4%