Our teacher divided us in 10 groups, in our group we had an argument they said in this problem
"Jenny makes extra money by selling homemade polvoron. The cost of making one polvoron is ₱25, and she sells each piece at ₱45. Her fixed cost each month -- consisting of her share of utilities, the materials, and ingredients -- is ₱1600."
25 is not included in the fixed cost which is 1600. They said that 25 is just a estimation, but for me if it is really an estimation why the word estimation itself isn't in the problem? Is 25 really not included ?
If she runs the business for one month and makes $x$ povlorons, her costs are $1600+25x$. Normally ingredients would be included in the variable cost, the $25$, because you need more ingredients the more povlorons you make. What is the difference between materials and ingredients? In any case, if she sells all she makes, her profit is then $45x-(1600+25x)=20x-1600$. Presumably there is a question you need this for. The constants $25, 45, 1600$ may be well known or may be estimates. In a book problem they are taken as known, but in real life you may not know them exactly. You should then see how the uncertainty changes your assessment of whether you are making or losing money.