A sold his pen at a profit of ₹13. He calculated the profit percentage on selling price and found it to be 20%. The cost price (in ₹) of the pen is:
Answer & explanation
Correct answer: option 1
Profit in rupees = 13
Profit at selling price = 20%
then CP : SP = 4x : 5x
x = 13
then, 4x = 52