Question

Neeraja bought a radio of 20% discount and sold it for rs.468 which is 4% more than the marked price what is the cost price of the radio?

Answer 1

let marked price = 100
so, cost price = 80
selling price = 104
when,
selling price = 104 then cost price = 80
so, when selling price = 468 then cost price = 80/104*468=Rs.360.

Answer 2

We don't know the original cost of the radio.  It is labeled at a marked price in the shop.  Instead of asking for the cost price of the radio,  the question should be at which price Neeraja bought the radio.

Marked price = MP
Neeraja bought it for  20% discount on the MP.  
  cost price of radio for Neeraja = (100 - 20)% of MP = 0.80 MP
    This is the selling price too at the shop.
  
  Neeraja sold it for Rs 468  =  MP + 4% MP = 1.04 MP

        MP = Rs 468 / 1.04 = Rs 450
 
  Cost price at which Neeraja bought it = 0.80 * Rs 450 = Rs 360