Something for Profit

             A friend of mine bought a used pressure cooker for Rs. 60. She somehow did not find it useful and so when a friend of hers offered her Rs. 70 she sold it to her. However, she felt bad after selling it and decided to buy it back from her friend by offering her Rs. 80. 

            After having bought it once again she felt that she did not really need the cooker. So she sold it at the auction for Rs. 90.

            How much profit did she make? Did she at all make any profit?

Answer: 

The woman made altogether Rs.20. She made Rs. 10 when she sold the item for the first time and another Rs. 10 when she sold it for the second time.