You want to subtract the total which is 71.4 minus the 1.21 ounces of the white chocolate, you then will get 70.19 ounces of dark chocolate. To be sure, you can add 70.19+1.21 and will get you the total amount of ounces of chocolate. Hope this helps :D
This is not factorable. It can be easily tested using the radicand expression of the quadratic equation. (Perfect square= Factorable, No Perfect= Not Factorable.)
