Answer: b = (Σy - m(Σx)) / n
Step-by-step explanation:
To find the linear regression equation, we need to calculate the slope and y-intercept using the given data points. The equation for a linear regression line is in the form y = mx + b, where m represents the slope and b represents the y-intercept.
Let's start by calculating the slope (m). The slope is given by the formula:
m = (Σ(xy) - (Σx)(Σy) / n(Σx^2) - (Σx)^2)
where Σ represents the sum, xy represents the product of x and y for each data point, Σx represents the sum of x values, Σy represents the sum of y values, and Σx^2 represents the sum of squared x values.
In this case, the given data points are:
x (homework grade): 85, 92, 78, 89, 94
y (test grade): 90, 87, 75, 92, 88
Let's calculate the necessary sums:
Σxy = (85 * 90) + (92 * 87) + (78 * 75) + (89 * 92) + (94 * 88)
Σx = 85 + 92 + 78 + 89 + 94
Σy = 90 + 87 + 75 + 92 + 88
Σx^2 = (85^2) + (92^2) + (78^2) + (89^2) + (94^2)
Now we can substitute these values into the slope formula:
m = (Σ(xy) - (Σx)(Σy)) / (n(Σx^2) - (Σx)^2)
Once we calculate the slope, we can move on to finding the y-intercept (b). The y-intercept is given by the formula:
b = (Σy - m(Σx)) / n
After finding both the slope and the y-intercept, we can write the linear regression equation y = mx + b.
Lastly, we can use this equation to estimate the homework grade (x) for a student with a test grade of 32. Simply substitute the given test grade (32) into the equation and round the result to the nearest integer.
I hope this helps :D