The percentage of loss when an article is sold at Rs. 50 is the same as that of the profit when it is sold at Rs. 70. The above mentioned percentage of profit or loss on the article is
Let the percentage of profit or loss on the
article be x.
C.P. at x% loss when S.P. is Rs. 50 = Rs. 50×100(100−x)
C.P. at x% profit when S.P. is Rs. 70 = Rs. 70×100(100+x)
∴50×100(100−x)=70×100(100+x)
⇒5(100+x)=7(100−x)
⇒500+5x=700−7x⇒12x=200
⇒x=20012=1623%