Problem 1 : The quantity demanded of the commodity in the market is 25 units when the selling price per unit is P12. Derive the demand equation given that because of the decrease in price to P8 per units, the quantity demanded increased to 60 units. Problem 2 : The quantity supplied of the commodity in the market is 30 units when the selling price per unit is P7. Derive the supply equation given that because of the increase in price to P10 per units, the quantity supplied of this commodity increased to 50 units