A shopkeeper offers 10% discount on the marked price of

A shopkeeper offers 10% discount on the marked price of his articles and still makes a profit of 20%. What is the actual cost of the article marked ₹ 500 for him ?

Given that , marked price = ₹ 500
Discount = 10% and profit = 20%
Let the cost price of article be p.

∴ 500 ×	90	=	120	× p
	100		100

⇒ 450 =	6p
	5

⇒ p =	450 × 5	= ₹ 375
	6

Second method :
C.P. = ? , M.P. = ₹ 500, r = 20%, D = 10%
Using the given formula ,

M.P.	=	100 + r
C.P.	=	100 − D

500	=	100 + 20
C.P.	=	100 − 10

C.P. =	500 × 90	= ₹ 375
	120