The number of newly reported crime cases in a county in New York State is shown in the accompanying table, where x represents the number of years since 2014, and y represents number of new cases. Write the linear regression equation that represents this set of data, rounding all coefficients to the nearest tenth. Using this equation, estimate the calendar year in which the number of new cases would reach 579.

The number of newly reported crime cases in a county in New York State is shown in the accompanying table where x represents the number of years since 2014 and class=

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The linear regression equation that represents this data set is equal to y = 120.8x + 2,114.

How to write the linear regression equation?

First of all, we would determine the slope of the given data set by using this formula:

[tex]Slope = \frac{\sum (x-\bar x)(y-\bar y)}{\sum (x-\bar x)^2}[/tex]

For the sample mean (years), we have:

[tex]\bar x = \frac{0\;+\;1+\;2\;+\;3\;+4}{5} \\\\\bar x =\frac{15}{4} \\\\\bar x =3.75[/tex]

For the sample mean (cases), we have:

[tex]\bar y = \frac{904\;+\;900+\;833\;+\;837\;+754}{5} \\\\\bar y =\frac{4,228}{4} \\\\\bar y =1057[/tex]

The sums are given by:

∑(x - |x|) = (0 - 3.75) + (1 - 3.75) + (2 - 3.75) + (3 - 3.75) + (4 - 3.75)

∑(x - |x|) = - 3.75 - 2.75 - 1.75 - 0.75) + 0.25

∑(x - |x|) = -8.75.

∑(x - |x|)² = (-8.75)² = 76.5625.

∑(y - |y|) = (904 - 1057) + (900 - 1057) + (833 - 1057) + (837 - 1057) + (754 - 1057)

∑(y - |y|) = -153 - 157 - 224 - 220 - 303

∑(y - |y|) = -1,057‬.

∑(x - |x|)(y - |y|) = -8.75 × -1057

∑(x - |x|)(y - |y|) = 9,248.75.

Now, we can determine the slope:

Slope = 9,248.75/76.5625

Slope = 120.8‬.

Therefore, the equation is given by:

y = 120.8x + a

Next, we would find the value of a:

1057 = 120.8(-8.75) + a

a = 1057 + 1,057

a = 2,114.

Hence, the linear regression model is given by:

y = 120.8x + 2,114.

Since the new cases would reach 579, the calendar year would be calculated as follows:

579 = 120.8x + 2,114

120.8x = 579 - 2,114

120.8x = -1,535

x = -1,535/120.8

x = -12.71.

Year = 2014 + 12.71

Year = 2026.712027.

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