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The mean and standard deviation of the amount x a company spends on advertising in a year (in thousands of dollars) are 67. 2 and 5. 4 respectively, and the mean and standard deviation of yearly revenue y are 738. 3 and 45. 5 respectively, and the correlation between x and y is 0. 87. The equation of the least squares regression line for predicting y from x is

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User MarkF
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Answer:y = 245.532 + 7.34 * x

Explanation:

To find the equation of the least squares regression line for predicting y from x, we need to use the given information about the means, standard deviations, and correlation.First, we calculate the slope, which is denoted as b1. The formula for b1 is (correlation * standard deviation of y) / standard deviation of x. In this case, the correlation between x and y is 0.87, the standard deviation of y is 45.5, and the standard deviation of x is 5.4. Plugging these values into the formula, we get b1 = (0.87 * 45.5) / 5.4 = 7.34.Next, we find the y-intercept, denoted as b0. The formula for b0 is the mean of y minus (b1 times the mean of x). Given that the mean of y is 738.3 and the mean of x is 67.2, we can calculate b0 = 738.3 - (7.34 * 67.2) = 738.3 - 492.768 = 245.532.Putting it all together, we can express the equation of the least squares regression line as y = 245.532 + 7.34 * x. This equation allows us to predict the value of y based on the given x value.

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User Ohadinho
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