A discount of 25% on one article is the same as a discount of 50% on another article. The costs of the two article can be:

A Rs 30, Rs 20

B Rs 90, Rs 40

C Rs 80, Rs 40

D Rs 50, Rs 40

Correct Answer: Option C

Let the costs of the two articles be x and y. Then,
25% of x = 50% of y
=> x/y = 50/25 = 2/1
So,x and y must be in the ratio of 2:1