By default if dealer C gave a discount of 12% instead of 15% then what will be the %  change in  sold articles after the discount. (Calculate approx value)

Let the cost price of the item is given as Rs. 25,000 Then marked price will be = (125/100) x 25,000 = Rs.31250 For Dealer A is, Let Cost price of the item is = 31250 x (70/100) = Rs.21875 Therefore Selling price will be 31250 x (85/100) = Rs.26562.5 For Dealer B is, Let Cost price of the item is = 31250 x (80/100) = Rs.25000 Let Selling price of the item is = 31250 x (75/100) = Rs.23437.5 For Dealer C is, Let Cost price of the item is = 31250 x (75/100) = Rs.23437.5 ATQ, Let marked price for dealer C is = Rs.31250 discount were used by default = (12% ) then SP 1 will be = 31250 x 88/100 = 27500 then Sp 2 will be = 31250  x 85/100 = 27327.5 now % change will be = (27500 - 27327.5) =  172.5 difference (172.5/27500) x 100 = 0.63% approx