Confidence Interval
Find the probabilistic boundary zone of the true population mean.
Intervalo de Confiança (95%)[71.42, 78.58]
Base Formula
IC = x̄ ± Z * (σ / √n)
Resolution
Média (x̄) = 75
Z (95%) ≈ 1.96
Erro Padrão = 10 / √30 = 1.8257
Margem de Erro = 1.96 * 1.8257 = 3.5785
Limite Inferior = 75 - 3.5785 = 71.42
Limite Superior = 75 + 3.5785 = 78.58
The Bounds of Research
There is no absolute certainty in sample statistics. If you ask 1,000 people whether they like chocolate, the \"Confidence Interval\" will stretch a margin of error around your mean. It scientifically guarantees: \"I am 95% sure that the REAL average of the entire country will fall within this tunnel of values that I calculated.\"