Question

selling price of an article is rupees 39. If numeral value of gain percent is equals to its C.P. then the C.P.of the article is​

Answer 1

Answer:

C.P of article is 30 rupees.

Step-by-step explanation:

Given Selling price of article is 39 rupees.

Let    Percent of Gain =X %

         cost price of article = X rupees   ( Given in  question )

Selling price = $cost price \times (1 + \frac{Percentage of gain}{100})$

39 = $X \times (1 + \frac{X}{100})$

3900 = $100 X + X^{2}$

$X^{2} + 100 X -3900 =0$

$X^{2} + 130 X - 30 X -3900 =0$

$X (X + 130) - 30 (X + 130) = 0$

$(X - 30)(X + 130) = 0$

From  X+130 =0 ⇒ X = - 130    Cost price is -130 Rupees which is not acceptable .

So  X - 30 =0  ⇒  X = 30       Cost price is 30  rupees

                                               Percent of gain is 30 %

Answer 2

step by step explanation