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Probability and Statistics

What is the main weight of all the apples in the orchard?

The scatter plot shows the relationship between the number of slices of pizza eaten by each member of a football team and the number of laps around the block the player could run immediately after. The equation of the regression line is shown in the graph: y^=100.67x\hat{y} = 10 - 0.67x. Interpret the slope and y-intercept.

A scatter plot shows the relationship between the amount of sugar added to water and the freshness of flowers. If the regression line is given by the equation y^=180.8+15.8x\hat{y} = 180.8 + 15.8x, interpret the slope and y-intercept.

Interpret the slope and intercept of the least squared regression line given by the equation score^=52.3+10.5×hours\hat{\text{score}} = 52.3 + 10.5 \times \text{hours}, where 'hours' represents the number of hours students studied for a test.

Find the marginal probability density function (PDF) of X given the joint probability density function of two continuous random variables, X and Y, is f(x,y)=23x+2yf(x, y) = \frac{2}{3}x + 2y for x1x \leq 1 and yy between ZZ and 1, and zero elsewhere.

Find the probability that X0.5X \leq 0.5 and Y0.5Y \leq 0.5 given the joint probability density function of two continuous random variables, X and Y, is f(x,y)=23x+2yf(x, y) = \frac{2}{3}x + 2y for x1x \leq 1 and yy between Z and 1, and zero elsewhere.

Given two random variables X and Y with a joint distribution as listed in the provided table, find the marginal distribution of X and Y, and calculate the expected values of X and Y.

Using the least squares method, find the equation of the line that best fits the given set of data points (x, y): (1, 1.5), (2, 3.8), (3, 6.7), (4, 9.0), (5, 11.2), (6, 13.6), (7, 16). Calculate the slope and the y-intercept of the line of best fit.

Using Excel, calculate the slope and y-intercept of the line of best fit for the given data points.

Calculate the least squares regression equation y^=β0+β1x\hat{y} = \beta_0 + \beta_1 x for the given small data set by hand. Find the estimates for the intercept β0\beta_0 and the slope β1\beta_1.

Given a set of data where the X values represent the number of questions correct out of a possible 20, and the Y values represent students' attitude percentages towards taking tests, use Simple Linear Regression to predict a student's attitude (Y) given a score (X). Specifically, calculate the slope (b) of the regression line using Pearson's correlation coefficient and standard deviations, determine the Y intercept (a), and use these to form the regression equation y=a+bxy = a + bx.

Given a training data set containing values for independent variable xx (e.g., height of a person) and dependent variable yy (e.g., weight), use linear regression to find the linear function g(x)=αx+βg(x) = \alpha x + \beta that best predicts yy from xx.

This involves finding the values of α\alpha (slope) and β\beta (intercept) that minimize the sum of squared differences between the observed values and the values predicted by the function.

An online poll asked a sample of 850 adult Americans whether they watched any World Cup soccer games. 62% of respondents said they did. What is the Margin of Error for this poll, rounded to the nearest tenth of a percent? What is the 95% confidence interval for the percent of all adult Americans who watched the World Cup?

What is the probability that our sample proportion of 0.54 is within two standard deviations of the population proportion?

With 95% confidence, what is the confidence interval for the proportion of voters supporting candidate A?

Find the marginal distribution for the gender variable. Calculate the total boys and total girls, and express them as percentages of the total sample size.

Find the marginal distribution for the color preference. Calculate the total for each color (red, blue, green), and express them as percentages of the total sample size.

In a classroom of 200 students, analyze the relationship between the amount of time studied and the percentage of correct answers. Given a two-way table, focus on calculating and interpreting marginal and conditional distributions.

Simplified binomial random variable problem: We have a binomial random variable with parameters NN and θ\theta. You flip a coin nn times with θ\theta as the probability of heads at each toss. After flipping, you observe a numerical value kk for random variable KK. Estimate θ\theta using maximum likelihood methodology.

Independent identically distributed normal variables problem: Given nn independent identically distributed normal random variables with unknown mean mu and variance vv, estimate mu and vv from these observations using maximum likelihood estimation.