How the proportion works
If a/b = c/d then d = (b × c) / a with a ≠ 0. Units must stay consistent. Inverse proportion is not covered.
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Enter three values and solve the fourth.
Data updated: 2026-08-12
Content updated: 2026-10-22
Sources
- Gelir İdaresi Başkanlığı
- SGK
- Çalışma ve Sosyal Güvenlik Bakanlığı
- EPDK
- Mevzuat Bilgi Sistemi
- CSGB / Asgari Ücret Tespit Komisyonu (2026 brüt/net)
- GİB gelir vergisi tarifesi 2026
- EPDK mesken elektrik kademeli tarife (yaklaşık)
- BOTAŞ / dağıtım şirketleri doğalgaz (yaklaşık)
- Hazine ve Maliye — kıdem tazminatı tavanı 1. dönem 2026
How is it calculated?
If a/b = c/d then d = (b × c) / a.
d = (b × c) / a
Official sources
Example
2/5 = 8/d → d = 20.
Guide
Solve for d in a/b = c/d proportion problems for recipes, scales, or allocations. Informational only.
2026 notes and common mistakes
Swapping the cross-multiply terms or mixing units are frequent errors.
Tips
- Keep paired quantities in matching units.
- For information only—label the result with units.
Sources: Basic mathematics · Proportion references
FAQ
Where is this useful? +
Scaling, mixtures, recipes and proportion problems.