Question

By selling an article for ₹ 144, a shopkeeper gains as much percent as the cost price. Find the cost price of the article.

Answer 1

Let the cost price of the article be ₹ x.

Selling price = ₹ 144

Gain = 144 − x

Gain percent = Cost Price

Gain percent = `"Gain"/"Cost Price" xx 100`

`(144-x)/x xx 100 = x`

100(144 − x) = x²

14400 − 100x = x²

x² + 100x − 14400 = 0

Factor:

(x + 180) (x − 80) = 0

x = −180 or x = 80

The cost price of the article is: ₹ 80​