I would choose the answer D
Answer:
a. Grand Mean = 2.799
b. Standard Deviation = 0.01387
c. Standard Error = 0.0016
d. The range with a Z score of 3 = (2.75739, 2.84061)
Step-by-step explanation:
a. Grand mean :
Given that
Sum of 80 values = 223.91
Total observation = 80
Grand mean = 223.91/80 = 2.799
b. With the excel command "STDEV[range of cells]", we get the standard deviation as = 0.01387
c. Standard error = Standard deviation / root of n

d. The range with a Z score of 3 :
lower limit = mean - (3 * SD) = 2.799 - (0.04161) = 2.75739
upper limit = mean + (3 * SD) = 2.799 + (0.04161) = 2.84061
Answer:
7868
Step-by-step explanation:
⇒ This can be written algebraically (with a variable <em>x</em>) as:
562 ÷ x = 14
⇒ Convert the division as a fraction:
= 14
⇒ Multiply both sides by 562 to get rid of the fraction and to isolate the variable <em>x</em>:
562 ·
= 14 · 562
⇒ Simplify:
x = 7868
<u>Answer:</u> 7868
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<em>Hope this helps!</em> :)
Answers:
The formula is [f(-1)-f(-4)]/[3]
The value of f(-1) is 3
The value of f(-4) is -3
The average rate of change is 2
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Explanation:
For the first blank, we use the formula
[ f(b) - f(a) ]/[ b - a ]
where 'a' and 'b' are the endpoints for the x interval
In this case, a = -4 and b = -1. When you plug those values into the formula above, you get...
[ f(b) - f(a) ]/[ b - a]
[ f(-1) - f(-4)]/[ -1 - (-4) ]
[ f(-1) - f(-4)]/[ -1+4 ]
[ f(-1) - f(-4)]/[ 3 ]
which is why the answer is choice C for the first blank
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To compute the value of f(-1), we draw a vertical line through -1 on the x axis. This vertical line crosses the diagonal function graph at the point (-1,3). The y value of this point is what we want. Plugging in x = -1 leads to y = 3. This is why f(-1) = 3
If you want, you can draw a horizontal line through (-1,3) and you'll see it touching 3 on the y axis.
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Follow similar steps as above to compute f(-4). Draw a vertical line through x = -4 on the x axis. Mark the point where the vertical line crosses the diagonal line. This point is (-4,-3). Optionally draw a horizontal line over til you hit the y axis and you'll find that y = -3 corresponds to x = -4
This is why f(-4) = -3
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We'll use the last three sections to compute the average rate of change. Everything combines together building up to this moment.
From the first part, we had the formula
[ f(b) - f(a) ]/[ b - a ]
[ f(-1) - f(-4)]/[ 3 ]
We can replace the "f(-1)" with 3 since we found that f(-1) = 3
Similarly, f(-4) = -3 so we can replace the "f(-4)" with -3
Doing those replacements and simplifying leads to...
[ f(-1) - f(-4)]/[ 3 ]
[ 3 - (-3)]/[ 3 ]
[ 3 + 3]/[ 3 ]
6/3
2
So the average rate of change is 2
Note: because the entire graph is a straight line, the average rate of change for any interval a < x < b is going to be equal to the slope m. In this case, the slope of the line is m = 2/1 = 2. We move up 2 units each time we move to the right 1 unit along the diagonal line.
Step-by-step explanation:
x² + 4x − 4 = 8
x² + 4x − 12 = 0
(x + 6) (x − 2) = 0
x = -6 or x = 2