After allowing a discount of 12% on the marked price, a

After allowing a discount of 12% on the marked price, a shopkeeper still gains 21%. The marked price is above the cost price by

Given that , discount = 12% and gains = 21%
C.P. of article = ₹ 100
Marked price be y .

∴	y × 88	= 121
	100

⇒ y =	121 × 100	= ₹ 137.5
	88

∴ 137.5 - 100 = ₹ 37.5 i.e. 37.5% above C.P.
Second method to solve this question :
Here, r = 12% , R = 21%
With the help of given formula ,

Required percentage =		r + R	× 100		%
		100 − r

Required percentage =		12 + 21		× 100%
		100 − 12

Required percentage =	33	× 100%
	88

=	3	× 100
	8

Required percentage =	300	% = 37.5%
	8