Answer:
2) B. as x increases, y increases as well
3) C. Number of books owned and number of visits to the doctor's office in one year
4) D. The 90 minute lesson that cost $40
5) A. There is a strong correlation
Step-by-step explanation:
2) i am not 100%positive since there is no way to check my answer, but i believe it is "B. As x increases, y increases as well" because it highlights the correlation between x and y.
(i already explained 3, 4, and 5 on another one :D)
Answer:
I think it is 52.
Step-by-step explanation:
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.
To write in slope intercept form solve the equation for y:
4x + 3y =15
Subtract 4x from both sides:
3y = -4x +15
Now get Y by itself by divide all terms by 3:
y = -4/3x + 5
