In microeconomics, the demand curve for a typical (normal) good has which of the following slopes in a price–quantity graph (price on the vertical axis, quantity on the horizontal axis)?

• A. A downward slope, indicating an inverse relationship between price and quantity demanded.
• B. A horizontal slope, indicating quantity demanded is perfectly elastic at all prices.
• C. An upward slope, indicating a direct relationship between price and quantity demanded.
• D. A vertical slope, indicating quantity demanded is perfectly inelastic at all prices.

Answer: (A)

Verified step by step guidance

1. Understand the axes of the graph: price is on the vertical axis (Y-axis) and quantity demanded is on the horizontal axis (X-axis).
2. Recall the Law of Demand, which states that, ceteris paribus, as the price of a normal good decreases, the quantity demanded increases, and vice versa.
3. Translate this relationship into the slope of the demand curve: since price and quantity demanded move in opposite directions, the demand curve slopes downward from left to right.
4. Recognize that a downward-sloping demand curve represents an inverse relationship between price and quantity demanded.
5. Contrast this with other slopes: a horizontal slope means perfectly elastic demand, an upward slope means a direct relationship (which is not typical for normal goods), and a vertical slope means perfectly inelastic demand.