# Can one Calculate Fixed and Variable Cost From TC and Quantity Alone?

I have been asked a question and believe there is a mistake in the problem.

I have been given a table of values, Quantity and corresponding Total cost. From those numbers I can easily calculate the Average total cost and marginal cost.

I am asked to find the fixed and variable cost for each quantity. The question provides no other information. Is this possible?

• @MB1992 I believe that with a little amount of mathematical notation added, this comment should be posted as an answer - after all that is all there is to it (and we do need to clear our "unanswered queue" as much as possible). Commented Nov 23, 2016 at 22:38
• Is your marginal cost constant? or do you have TC(0) in your table ?
– Yann
Commented Nov 24, 2016 at 11:18

## 1 Answer

As said in my comment,

The fixed cost is usually defined as the cost when quantity is equal to zero, and the variable cost as the total cost minus the fixed cost.

Hence, if $TC(q)$ is the total cost for the given level of quantity $q$, then $FC=TC(0)$ is the fixed cost, which is a constant independent of $q$; and $VC(q)=TC(q)-FC$ is the variable cost.

For example, if $TC(q)=10+q$, then $FC=TC(0)=10$ and $VC(q)=TC(q)-FC=q$.