Considere una variable continua x que tiene una distribución normal con media $\mu = 93$ y desviación estándar $\sigma = 8$. 1. El percentil 23 ($P_{23}$) de la distribución es 2. Los valores de x que acotan el 11 % medio de la distribución son ? frontera inferior es ? frontera superior es 3. El valor estándar z de x = 97 es 4. El error estándar ($\sigma_{\bar{x}}$) de la distribución de medias muestrales de muestras de tamaño 159 es 5. Si se elige al azar una muestra de tamaño 194 de la población, la probabilidad que esta muestra tenga un promedio menor que 91 es
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