In standard microeconomic theory, a short-run production function assumes that at least one input is fixed while other inputs can be varied.

### Why this is right The stated assumptions distinguish inputs that are fixed from those that can vary and treat inputs and outputs as finely divisible. These assumptions simplify production analysis. ### The concept An assumption makes a model easier to analyze, but real firms may face indivisibilities or constraints. Managers should recognize the difference between the analytical setting and actual operations. ### Remember Know the assumptions behind a production model before applying its conclusions.