Answer:
<em>A: For each increase in the number of procrastination days by 1, the predicted grade decreases by 3.64 points.</em>
Step-by-step explanation:
<u>The slope of a Regression Line</u>
A straight line can be represented in the slope-intercept form:
y = mx + b
Where m is the slope and b is the y-intercept.
The slope describes how fast and in what direction the graph goes when x changes values.
If m is positive, increments in x imply increments in y.
If m is negative, increments in x imply decrements in y.
The regression line is:
ŷ = –3.64x + 96.5
Where:
x = the number of procrastination days
ŷ = the predicted grade
We can say the slope is m=-3.64. This means that:
A: For each increase in the number of procrastination days by 1, the predicted grade decreases by 3.64 points.
Ni : Zn: Cu = 7:2:9 =7x : 2x : 9x
7x+2x+9x = 3.8
18x=3.8
x=3.8/18=1.9/9≈0.21
Ni: 7x=7*0.21=1.47 ≈1.5 kg
Zn: 2x=2*0.21=0.42≈0.4 kg
Cu: 9x=9*0.21=1.89 ≈1.9 kg
Check 1.5+0.4+1.9 =3.8 True
All u need to do is subtract the bigger number from the smaller one
P(A) =0.54
P(B)= 0.68
P'(A)= 1-0.54 = 0.46
P'(B)= 1- 0.68 = 0.32
The probability of neither of both event will occur:
= P'(A)×P'(B)
=0.46 × 0.32
=0.1472