I am assuming that you are looking for the price elasticity of demand.
Price elasticity of demand = percentage change in quantity demanded
percentage change in price
Quantity demanded: from 403,000 to 549,000
Change in demand: 549,000 - 403,000 = 146,000 increase in sales
percentage change: 146,000 / 403,000 = 0.36 or 36% increase
Price: from 2,500 to 2,300
Change in Price: 2,300 - 2,500 = -200 decrease in price
percentage change: 200 / 2,500 = 0.08 or 8% decrease
Price elasticity of demand = 36% / 8% = 4.5
Since the price elasticity of demand is greater than 1, it means that the demand of the product is greatly affected by the price of the product.