Final answer:
The quantity demanded is likely to decrease when the price of a product increases from Php 150 to Php 200, following the law of demand, but without specific data on demand elasticity, an exact numerical approximation cannot be provided.
Step-by-step explanation:
The question pertains to the concept of demand elasticity, which is grounded in the basic principles of economics and essentially examines how the quantity demanded of a good or service is affected by changes in its price. Given that at a price of Php 150 the demand is 500 units, and considering the examples provided, we could infer that as the price increases to Php 200, the demand would likely decrease, assuming the law of demand holds true—higher prices typically lead to lower quantity demanded, if all other factors remain constant (ceteris paribus).
In the absence of specific data on the exact demand curve and its elasticity, we cannot provide an exact numerical approximation. Moreover, without additional context such as consumer preferences, the nature of the good, the degree of necessity or luxury, and the presence of substitutes, among other factors, making an accurate prediction is not possible.
However, the general principle suggests that there would be a reduction in demand; the extent of this reduction would depend on the aforementioned factors and the elasticity of demand for the good.