Answer:
For The Second One
The Answer Is 15
Step-by-step explanation:
a. To find the least squares regression equation for a group of (x,y) points:
Step 1: For each point(x,y), we need to calculate x² and xy first.
Step 2: Sum all x, y, x² and xy, which gives us Σx, Σy, Σx² and Σxy
Step 3: Calculate Slope m: m = (NΣxy − Σx Σy)/ N(Σx²) − (Σx)² , here N is the number of data.
Step 4: Calculate Intercept b: b = Σy − m(Σx)/ N
Step 5: Assemble the equation as y= mx+b
Here, we have ∑x = 120, ∑y= 1379, ∑x²= 919.5, ∑xy= 10466 and N= 16
So, m= (NΣxy − Σx Σy)/ N(Σx²) − (Σx)²
=
=
=
= 6.33
and b = Σy − m(Σx)/ N
=
=
=
= 38.71
So, the least squares regression equation is : y= mx+b ⇒ y= 6.33x +38.71
b. When x= 8, then y= (6.33×8)+38.71 = 50.64 + 38.71 =89.35
The approximate test score of a student who sleeps an average of 8 h a night is 89.35%
Step-by-step explanation:
42+5x+7x+6=180 (sum of angles in straight line is 180)
- 48+12x=180
- 12x=180-48
- 12x=132
- x=132/12
- x=11
now m <CBE =7x+6=7×11+6=77+6=83
Depends on the original point
1. A, It goes past the 4, but the circle is not shaded because the answer cannot be 4
2. C. It goes below the 11 and is shaded because it can be equal to 11
3. D. It is less than 13 and cannot equal thirteen, hence the non shaded circle
4. B. I goes past the -2 and has the circle shaded because it can be equal to the -2