Respuesta :
Answer: y=374.2 -133 x
Step-by-step explanation: I just did the khan test
Least-squares regression equation
The equation for the least-squares regression line for predicting yyy from xxx is of the form:
\hat{y}=a+bx
y
^
=a+bxy, with, hat, on top, equals, a, plus, b, x,
where aaa is the yyy-intercept and bbb is the slope.
Hint #22 / 4
Finding the slope
We can determine the slope as follows:
b=r\left(\dfrac{s_y}{s_x}\right)b=r(
s
x
s
y
)b, equals, r, left parenthesis, start fraction, s, start subscript, y, end subscript, divided by, s, start subscript, x, end subscript, end fraction, right parenthesis
In our case,
b=-0.95\left(\dfrac{42}{0.3}\right)=-133b=−0.95(
0.3
42
)=−133b, equals, minus, 0, point, 95, left parenthesis, start fraction, 42, divided by, 0, point, 3, end fraction, right parenthesis, equals, minus, 133
Hint #33 / 4
Finding the yyy-intercept
Because the regression line passes through the point (\bar x, \bar y)(
x
ˉ
,
y
ˉ
)left parenthesis, x, with, \bar, on top, comma, y, with, \bar, on top, right parenthesis, we can find the yyy-intercept as follows:
a=\bar y-b\bar xa=
y
ˉ
−b
x
ˉ
a, equals, y, with, \bar, on top, minus, b, x, with, \bar, on top
In our case,
a=41.7 +133 (2.5)=374.2a=41.7+133(2.5)=374.2
