A small shop in Bulacan fabricates portable threshers for palay producers in the locality. The shop can produce each thresher at a labor cost of P1,800. The cost of materials for each unit is P2,500....

Extracted text: A small shop in Bulacan fabricates portable threshers for palay producers in the locality. The shop can produce each thresher at a labor cost of P1,800. The cost of materials for each unit is P2,500. The variable costs amount to P650 per unit, while fixed charges incurred per annum totals P69,000. If the portable threshers are sold at P7,800 per unit, how many units must be produced and sold per annum to break-even? Support your answer with computations and also by graphical solution.