Question

If a shopkeeper marks his goods for a certain amount so as to get 25% gain after allowing a discount of 20% , then his market price is ?

Answer 1

Cp=100
Sp =100*125/100=125
Mp=100*125/80=156.25

Answer 2

I don't think that there is one possible answer for this question and can be stated as incomplete. For getting a relation you can assume CP=100 followed by SP=125 and hence Marked Price=156.25. If you assume CP=200, you will get a different value for Marked Price.