If a buyer buys less of a commodity when his income falls, how will his demand curve change? Illustrate your answer with a diagram.
A buyer will buy less commodities with a fall in income for a normal good. Such a situation is known as a decrease in demand. The given figure represents the situation of a decrease in demand. In the figure, OP is the original price at which the quantity demanded is OQ. With a fall in income, demand decreases to D1.