Break-even formula: "Total cost= total revenue". (Total revenue= 75 × N) while (Total cost= 100,000 + [(23+37+1)×N]. So the equation now would be "100,000+ [(23+37+1)×N]= 75 × N". Solving for N... 14N=100000... N=7142.9 sets~~ 7143 sets. Therefore, 7143 sets must be produced per month to break-even...