First, you must turn 25% into decimal form. To do that, you must divide by 100 to get 0.25.
25%/100=0.25
Next, you must multiply the cost of the TV by the sales price.
1250(0.25)= 312.50
$312.50 is the money you take off of the original price, also known as the discount or the sales price. (Extra info if it is needed) If you are looking for the price of the TV with the discount, you would subtract the discount from the original cost of the TV. i.e. 1250-312.50=937.50.
Hope this was helpful.