Durante el 2003 los precios de la gasalina alcanzaron record de precios altos en 16 estados de Estados Unidos (The Wall Street Journal, 7 de marzo de 2003 ). Dos de los estados afectados fueron California y Florida. La American Autamabile Association encontró́ como precio medio muestral por galán \( \$ 2.04 \) en California y \( \$ 1.98 \) por galón en Florida. Use 40 como tamario de la muestra de California y 35 como tamaño de la muestra en Florida. Suponga que estudios anteriores indican que la desviación estándar poblacional en California es 0.10 y en Flarida 0.09 . ¿Existe diferencia entre los precios a un nivel de significancia de 0.01 ?

In a normal distribution, a data value located 1.4 standard deviations below the mean has Standard Score: \( \mathrm{z}=-1.4 \) In a normal distribution, a data value located 2.3 standard deviations above the mean has Standard Score: \( \mathrm{z}=2.3 \) In a normal distribution, the mean has Standard Score: \( \mathrm{z}=\square \)

A set of exam scores is normally distributed with a mean \( =74 \) and standard deviation \( =8 \). \( 95 \% \) of the data values lie between 58 \( \% \) of the exam scores are between 66 and 74 . \( \% \) of the exam scores are between 74 and 90 . \( \% \) of the exam scores are between 82 and 90 . \% oxam scores are greater than or equal to 66 .

A variable is normally distributed with mean 18 and standard deviation 9 . Use your graphing calculator to find each of the following areas. Write your answers in decimal form. Round to the nearest thousandth as needed. a) Find the area to the left of 17.

1.3.1 Bereken die gemiddelde aantal huishoudings in Suid-Afrika wat gedurende 2022 nie toegang tot die internet gehad het nie.

Which of the following statements are TRUE about the Normal Distribution? Check all that apply. The graph of the Normal Distribution is bell-shaped, with tapering tails that never actually touch the horizontal axis. \( 50 \% \) of the data values lie at or above the mean. about \( 95 \% \) of all data values lie within 1 standard deviation of the mean. The mean, median and mode are all equal and occur at the center of the distribution. Data values are spread evenly around the mean. Data values farther from the mean are less common than data values closer to the mean.