The correct option is B 4% loss
Let the selling price of each article be 120.
Now, we have 20% profit at first; so,
⇒ 120% of CP1 = 120
⇒ CP1 = 120 × (100/120) = 100
Also, we have 20% loss; so,
⇒ 80% of CP1 = 120
⇒ CP1 = 120 × (100/80) = 150
Hence,
Total SP = 120 + 120 = 240
Total CP = 100 + 150 = 250
Loss = 250 – 240 = 10
Loss% = (10/250) × 100 = 4%
Short Cut-
If the selling price is the same and we have the same percentage of profit and loss,
there will always be a loss of (x2100)%=202100%=4% loss.