In the cost price of 12 pens is equal to the selling price of 16 pens, find the loss per cent.

Question: In the cost price of 12 pens is equal to the selling price of 16 pens, find the loss per cent.

Solution:
Let the C.P. of 1 pen =Tk. 1
∴ C.P of 12 pens=Tk. 12×1 =Tk. 12

C.P. of 12 pens = S.P of 16 pens
∴ S.P of 16 pens= Tk. 12
∴ C.P of 16 pens= Tk. 16


∴ Loss = C.P - S.P
=16- 12
=4 Tk.

Loss = {(4/16​) × 100}%
= 25%.