A man makes a profit of 20% after selling a product on 28% discount on the printed price. Find the ratio of printed price to cost price.

5 : 3

Profit (P)% = 20%

S.P. = C.P. × 120%  ..........(i)

Discount (D)% = 28%

S.P. = M.P. × 72%   ...........(ii)

S.P. in both cases is equal, (i) = (ii):

⇒ C.P. × 120% = M.P. × 72%

⇒ C.P. × 5 = M.P. × 3

⇒ M.P. : C.P. = 5 : 3