II. (Valor \( 35 \% \) ) El puntaje promedio de ciertos estudiantes en una prueba de aptitud es de 72 puntos con una varianza de 36 puntos. ¿Cuál es la probabilidad de que dos grupos de 28 y 36 estudiantes, respectivamente, difieran en sus puntajes promedio por 1. 3 puntos o más 2. Entre 2 y 5 puntos?

Which of these values of the correlation coefficient indicates the weakest relationship between two variables? -0.30 -0.18 0.03 0.42

Activity 1 (Measures of Relative Position) Kindly answer this by group, with at most 5 members for each group. Answer this on a whole sheet of paper. 1. Median Income: In 2009 , the median family income in the United States was \( \$ 49,777 \). (Source: U. Census Bureau) If the 90 th percentile for the 2009 four-person family income was \( \$ 137,632 \), find th percentage of families whose 2009 income was a. more than \( \$ 49,777 \). b. more than \( \$ 137,632 \) c. between \( \$ 49,777 \) and \( \$ 137,632 \)

Test the claim that the proportion of people who own cats is significantly different than \( 10 \% \) at the 0.2 significance level. The null and alternative hypothesis would be: \( H_{0}: p=0.1 \quad H_{0}: p=0.1 \quad H_{0}: \mu=0.1 \quad H_{0}: \mu=0.1 \quad H_{0}: p=0.1 \quad H_{0}: \mu=0.1 \) \( H_{1}: p \neq 0.1 \quad H_{1}: p<0.1 \quad H_{1}: \mu \neq 0.1 \quad H_{1}: \mu>0.1 \quad H_{1}: p>0.1 H_{1}: \mu<0.1 \) The test is: right-tailed left-tailed two-tailed Based on a sample of 700 people, \( 8 \% \) owned cats The test statistic is: \( -\quad \) This is not a decimal or integer value. (to 4 decimal places) The p-value is:

The first step involved in calculating the Pearson correlation coefficient is to sum all the scores square all the scores calculate the standard deviation for each variable

9 A \( 99 \% \) confidence interval for the mean mass of steel sheets produced in a factory is \( (30.37 \mathrm{~kg}, 32.43 \mathrm{~kg}) \). This interval is based on a random sample of 36 steel sheets. Find a \( 95 \% \) confidence interval for the mean mass of steel sheets, assuming that the masses of steel sheets are normally distributed.