how much did they sale? you can not complete the answer without a sale amount. because you are asking that they made $1,200 plus 3% of sale, but you do not have the amount they sold so it just $1,200+3% of the sale , but no number for how much they sale, but for advice i would get the total amount they sale and divide by 100 then times it by 3 then try to fill in the void on how they went from 1,200 to 2500. You need to tell us the amount they sold and then the we can answer your question, but without you will not get your answer, so your question is incomplete.
N can be equal to anything below 4 because if they are integers, m will equal to 5 or lower, as long as it is a whole number, but since the greatest possible answer is 5 then we will say m=5. So it is simplified to 6<5<n, and same thing, n is equal to any whole number below 5, so n is equal to 4, 3, 2, 1, 0, etc.
119/100 in simplest form and as a fraction