we have the price of TV is $3960.if we round off to the nearest tens we get same 3960 because we have 0 at the end which means lesser than 5 so 60 will be the nearest ten.
discount =[tex] \frac{25}{100} *3960=990 [/tex]
so $990 will be the discount.
and the cost of TV after discount is [tex] 3960-990=$2970 [/tex]