Can someone help me in this maths finance (EMI ) query?

One of my friend has taken a loan of 100000 at 10% for 10 years on monthly reducing rate and he was supposed to pay a monthly installments of 1328 for 10 years. He has already paid 46 installments ( 1328 x 46 = 61088 ) and now want to pay the balance amount fully. How much is the balance now he has to pay to liquidate the full loan amount. He has already paid 61088 so after deducting 61088 from 100000 the balance is 38912 but every month interest will have been applied on the amount of principal left after paying monthly installment and I want to know what is that total interest and if possible please let me know a simple formula to calculate this.