Aprender
Calcular qué fracción de un total representa un valor, expresado como porcentaje.
A percentage expresses a value as a fraction of 100. To find what percentage a part is of a whole: divide the part by the total, then multiply by 100. Percentages are fundamental to pie charts (which always sum to 100%) and for comparing proportions across different totals.
percentage = (part / total) × 100
- 15 out of 60 = 15/60 × 100 = 25%
- If a pie slice is 40°, it represents 40/360 × 100 ≈ 11.1%
- 200 out of 800 total = 200/800 × 100 = 25%
Cómo reconocerlo
- Questions asking 'what percentage' or 'what fraction'
- Pie chart slices (each represents a percentage)
- Comparisons asking for relative size
Errores comunes
- Dividing total by part instead of part by total
- Forgetting to multiply by 100
- Confusing percentages with absolute values
Resolución paso a paso
Una encuesta preguntó a 60 personas su bebida favorita. 15 dijeron café. ¿Qué porcentaje prefiere café?
- Observe el gráfico circular: encontrar qué porcentaje representa el segmento de Café
- Identificar la parte y el total: Parte = 15, Total = 60
- Aplicar la fórmula: (parte ÷ total) × 100
- Calcular: 15 ÷ 60 = 0.25
- Multiplicar por 100: 0.25 × 100 = 25%
Respuesta: 25%