Answer:
Step-by-step explanation:
It is given that the regression equation
predicts an adult’s height (y) given the individual’s mother’s height (x1), his or her father’s height (x2), and whether the individual is male (x3 = 1) or female (x3 = 0).
The coefficient of x1 = 0.32 represents the increase in height of the child due to one inch increase in mother.
Similarly coefficient of x2 = 0.42 represents the increase in height of the child due to one inch increase in father.
and coefficient of x3 = 5.31 represents the increase in height of the child due to being a male than a female.
Answer:
1.6
Step-by-step explanation:
8/5=1.6
1.6 x 5 = 8
You need to understand that you're solving for the average, which you already know: 90. Since you know the values of the first three exams, and you know what your final value needs to be, just set up the problem like you would any time you're averaging something.
Solving for the average is simple:
Add up all of the exam scores and divide that number by the number of exams you took.
(87 + 88 + 92) / 3 = your average if you didn't count that fourth exam.
Since you know you have that fourth exam, just substitute it into the total value as an unknown, X:
(87 + 88 + 92 + X) / 4 = 90
Now you need to solve for X, the unknown:
87
+
88
+
92
+
X
4
(4) = 90 (4)
Multiplying for four on each side cancels out the fraction.
So now you have:
87 + 88 + 92 + X = 360
This can be simplified as:
267 + X = 360
Negating the 267 on each side will isolate the X value, and give you your final answer:
X = 93
Now that you have an answer, ask yourself, "does it make sense?"
I say that it does, because there were two tests that were below average, and one that was just slightly above average. So, it makes sense that you'd want to have a higher-ish test score on the fourth exam.
It's always easier to understand a concept by looking at specific examples with pictures, so I suggest looking at the dilation examples below first...before you try to internalize the steps listed below and that explain the general formula for dilating a point with coordinates of (2,4) by a scale factor of <span><span>12</span><span>12</span></span>.
<span><span>1) multiply both coordinates by scale factor<span>(<span><span>2⋅<span>12</span>,4⋅<span>12</span></span><span>2⋅<span>12</span>,4⋅<span>12</span></span></span>)</span></span><span>2)
2. Simplify(1,2)</span><span>3)
3. Graph(if required)<span> </span></span></span>
Answer:
1. x = 3/2 = 1.500
2. x = ± √3 = ± 1.7321
Step-by-step explanation:
