Abhi bought two articles for Rs. 624. He sold one at loss of 15% and another at a profit of 15%. If the selling price of both articles is equal. Then the difference between their cost price is?

93.6

15% = \(\frac{3}{20}\)                            

               CP        :       SP                                                 

+15%⇒   20        :       23     )× 17                                    

-15% ⇒   20        :       17     )× 23

*(to make S.P. equal, ATQ)*              

             CP       :       SP

⇒          340      :      391

⇒          460      :      391

Total C.P. = 800R and diff. of C.P. = 460 -340 = 120R

800R = 624

1R = \(\frac{624}{800}\) = \(\frac{78}{100}\)

120 R = 120 × \(\frac{78}{100}\) = Rs. 93.6