Correct Answer - Option 3 : Rs. 400
Given:
C.P of two articles is Rs.1000
He sold the first article at 20% profit and the second article at 20% loss.
Their selling prices are equal.
Formula used:
{C.P × (100 + Profit%)}/100 = S.P
Also, {C.P × (100 - Loss%)}/100 = S.P
Where, C.P = Cost, price S.P = Selling price
Calculation:
Let the C.P of the first article be x and the second article be y
He sold the first article at 20% profit.
So, S.P of first article = {x × (100 + 20)}/100 = 120x/100
He sold second article at 20% loss.
So, S.P of second article = {y × (100 – 20)}/100 = 80y/100
Now, their selling prices are equal.
Then, 120x/100 = 80y/100
⇒ 3x = 2y
⇒ x/y = 2/3
Then, we can say x = 2 part and y = 3 part
So, the total part is 5 part which is equal to the C.P of the two articles.
⇒ 5 part = 1000
⇒ 1 part = 200
⇒ 2 part = 2 × 200
⇒ 400
∴ The cost price of the first article is Rs. 400.
