StudyDeck

Individual & Market Supply

Exam code: 2281
Written by: Ashika|Reviewed by: Caroline Carroll|Updated 2 July 2026

Defining supply

Defining supply

  • Supply is the amount of a good/service that a producer is willing and able to supply at a given price in a given time period

  • The law of supply states that there is a positive (direct) relationship between quantity supplied and price, ceteris paribus

    • When the price rises, the quantity supplied rises

    • When the price falls, the quantity supplied falls

Individual and market supply

  • Market supply is the combination of all the individual supply for a good/service

    • It is calculated by adding up the individual supply at each price level 

The monthly market supply of bread from 4 bakeries in a small town

Bakery 1

Bakery 2

Bakery 3

Bakery 4

Market Supply

300

600

180

320

1400 loaves

Drawing and interpreting a supply diagram

Drawing and interpreting a supply diagram

  • A supply curve is a graphical representation of the price and quantity supplied by producers

    • If data were plotted, it would be an actual curve

    • Economists, however, use straight lines to make analysis easier 

  • The supply curve is sloping upward, as there is a positive relationship between the price and quantity supplied

    • Rational profit maximising producers would want to supply more as prices increase in order to maximise their profits 

  • Individual and market supply can also be represented graphically
     

    Three supply graphs show iPhone, Samsung, and total supply at $1,000. Quantities: iPhone 300, Samsung 320, Total 620. Green lines indicate supply increase.
    Market supply for smart phones in December is predominantly the combination of iPhone and Samsung supply

Diagram analysis

  • In New York City, the market supply for smartphones in December is predominantly the combination of iPhone and Samsung supply

  • At a price of $1000, the supply of iPhones is 300 units and the supply of Samsung phones is 320 units

  • At a price of $1,000, the market supply of smartphones in New York City during December is 620 units