So from what I understand of the problem, the tv costs $850 at a discounted price of 20%. and other than the 20%, you can get an additional discount of 15% at the counter. So to solve this, you can just simply multiply 850 with 35% or 0.35. The answer to that will be $297.5. Now you then have to less this amount with 850. The final answer to that is 552.5. So after all the discounts that you have received from the store, then the final price that you can get for this tv set would be $552.5