Suppose there are only two normal goods in the economy, X and Y. If pr

Suppose there are only two normal goods in the economy, X and Y. If price of good X increases, which would be the correct statement from below ?

Demand for good X decreases and demand for Y is indeterminate.
Demand for good X decreases and demand for Y decreases.
Demand for good X increases and demand for Y is indeterminate.
Demand for good X increases and demand for Y decreases.
This question was previously asked in
UPSC CDS-2 – 2024
The correct option is A. The question describes a scenario with two normal goods (X and Y) and asks about the effect of an increase in the price of good X.
If the price of good X increases, according to the Law of Demand, the quantity demanded of good X will decrease, assuming all other factors remain constant (ceteris paribus). This is a movement along the demand curve for X.
To determine the effect on the demand for good Y, we need to consider the cross-price elasticity of demand, which depends on whether X and Y are substitutes, complements, or unrelated goods.
– If X and Y are substitutes (e.g., tea and coffee), an increase in the price of X makes Y relatively cheaper or more attractive. This leads to an increase in the demand for Y (a rightward shift of the demand curve for Y).
– If X and Y are complements (e.g., cars and petrol), an increase in the price of X reduces the quantity demanded of X. Since X and Y are consumed together, the reduced consumption of X also leads to a decrease in the demand for Y (a leftward shift of the demand curve for Y).
– If X and Y are unrelated goods, a change in the price of X has no significant impact on the demand for Y.
The information that X and Y are “normal goods” relates to how their demand changes with income, not how their demand changes with respect to the price of *another* good. Therefore, based only on the information that X and Y are normal goods and the price of X increased, we know the demand for X decreases, but the effect on the demand for Y is indeterminate without knowing the relationship between X and Y (substitutes, complements, or unrelated).
Option A correctly states that demand for X decreases and demand for Y is indeterminate. Options B, C, and D make specific claims about the demand for Y (decreases, increases) or demand for X (increases), which are either incorrect or not universally true given only the information provided.