A solution to a system of equations where all variables are non-zero. For example, outputs of all goods are positive, or all prices are positive. This is contrasted with a corner solution, in which some variables are zero. Statements of optimality conditions in terms of equality of marginal costs and marginal benefits are correct only for interior solutions.

• finance, public
• financial assets
• financial deregulation
• financial derivative
• financial futures
• financial innovation
• Financial Intermediaries, Managers and Brokers Regulatory Association
• financial intermediary
• financial markets
• financial ratios
• financial repression
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• financial year
• financing, official
• fine tuning
• firm
• firm-specific human capital
• first-best