Respuesta :

SP = 400

Loss = 20%

CP = x

CP = SP + 20%CP

Therefore,

x = 400 + 20/100x

x = 400 + 1/5x

x - 1/5x = 400

5/5x - 1/5x = 400

4/5x = 400

x = 400 × 5/4

x = 100 × 5

x = 500