Something that is logically or factually sound

Having legal force or effectiveness

कानूनी

English Usage: His driver's license is still valid.

Hindi Usage: उसका ड्राइविंग लाइसेंस अभी भी कानूनी है।

A mathematical statement that asserts the equality of two expressions

A situation or problem that can be expressed mathematically

परिस्थितिकी

English Usage: Finding the right balance is an important equation in project management.

Hindi Usage: सही संतुलन खोजना परियोजना प्रबंधन में एक महत्वपूर्ण परिसंख्या है।