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Updated Mar 27, 2026

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2 pages

Understanding Total, Fixed, and Variable Costs in Microeconomics

Sana

@sana_ilzu

Understanding business costs is crucial for analysing how companies make... Show more

# COSTS!

Short vs. Long Run

The short run is where at least one factor of
production is fixed.

The long run is where all factors are vari

Short Run vs Long Run and Cost Types

The short run is when at least one factor of production (like machinery or factory space) is fixed and can't be changed. In contrast, the long run allows businesses to adjust all their factors of production - they can buy new equipment, hire more staff, or move to bigger premises.

Variable costs change directly with how much you produce. Think of The Guardian newspaper - if they print more copies, they'll need more ink, paper, and possibly overtime wages. These costs go up and down with output levels.

Fixed costs stay the same regardless of production levels. The Guardian still pays the same rent for their offices and the same salaries to permanent staff whether they print 10,000 or 100,000 newspapers. Equipment costs, rent, and regular salaries are typical fixed costs.

The total cost formula is straightforward: Total Cost = Total Variable Cost + Total Fixed Cost. This helps businesses understand their complete cost structure.

Quick Tip: Remember that fixed costs are only "fixed" in the short run - eventually, even rent and equipment can be changed!

Understanding Fixed Cost Curves

Total Fixed Costs (TFC) appear as a horizontal line on a graph because they don't change with quantity produced. Whether a company makes 1 unit or 1,000 units, total fixed costs remain constant.

Average Fixed Costs (AFC) tell a different story entirely. The formula is: AFC = Total Fixed Costs ÷ Quantity. As production increases, you're spreading the same fixed costs across more units, making each unit cheaper to produce.

This creates the famous "Always Falling AFC curve" - a downward sloping curve that never quite reaches zero. The more you produce, the smaller your average fixed cost per unit becomes, which is why mass production can be so profitable.

Remember, both TFC and AFC only exist in the short run since that's when factors are fixed. In the long run, businesses can adjust everything, so these concepts become less relevant for long-term planning.

Memory Hook: AFC = "Always Falling Curve" - this nickname will help you remember its shape in exams!

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Economics

•

Updated Mar 27, 2026

•

2 pages

Understanding Total, Fixed, and Variable Costs in Microeconomics

Sana

@sana_ilzu

Understanding business costs is crucial for analysing how companies make decisions about production and pricing. We'll explore the difference between short-run and long-run costs, and how fixed and variable costs behave as output changes.

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Short Run vs Long Run and Cost Types

The total cost formula is straightforward: Total Cost = Total Variable Cost + Total Fixed Cost. This helps businesses understand their complete cost structure.

Quick Tip: Remember that fixed costs are only "fixed" in the short run - eventually, even rent and equipment can be changed!

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

Understanding Fixed Cost Curves

Total Fixed Costs (TFC) appear as a horizontal line on a graph because they don't change with quantity produced. Whether a company makes 1 unit or 1,000 units, total fixed costs remain constant.

Memory Hook: AFC = "Always Falling Curve" - this nickname will help you remember its shape in exams!