Percentage — Formulas & Shortcuts
Curated by Prabhakar Bhatt, Founder of क्रांति · Last reviewed 2 July 2026
# Percentage — Quick Reference
## Core formulas
- Percentage change = ((New − Old) / Old) × 100
- Successive % change: a + b + (ab/100)
- x% of y = y% of x
## Common conversions
- 1/2 = 50%, 1/4 = 25%, 1/5 = 20%, 1/8 = 12.5%
## Short trick
MP 40% above CP with 20% discount ⇒ SP = 1.4×0.8 = 1.12 CP ⇒ 12% profit.