9. The average price of a home in W County rose more than 12% last year but the number of sales fell nearly 15%. Its the old law of supply and demand, said a spokesman for the Board of Realtors. The number of sales is down because there's a higher demand for properties but there isn't a corresponding number to sell. What does the old law of supply and demand predict would happen to price and quantity if the demand curve shifts outward and the supply curve does not change