The last payment would be $30. This is computed by solving first the total amount of computer including 8% tax, so 1,250 times 8% is equal to 100, then 100 plus 1,250 is 1,350. Then 1,350 will be divided by 120, which is equal to 11.25. Getting the 0.25, from 11.25, multiply be 120 (0.25 times 120), is equal to $30.
