LESSON 5 · Math You Actually Use
Budget Proportions
The classic 50/30/20 rule divides income into three categories: 50% for needs, 30% for wants, 20% for savings. On a $4,000 monthly income, that's $2,000 for needs, $1,200 for wants, and $800 for savings. Treat these proportions as starting guidelines you adjust for local cost of living and personal priorities.

Home improvement budgets use similar thinking. Allocate 1-3% of home value annually for maintenance. A $300,000 home: $3,000-$9,000/year for upkeep. Spreading this across 12 months means setting aside $250-$750 monthly. The math prevents surprise expenses from becoming financial emergencies.