It should be 2,736? I think? I multiplied the fourth graders number x 4 and that’s what I got, I hope it’s correct!
Answer:
Lower confidence limit = 20.191
Step-by-step explanation:
Sample mean; x' = 22
Sample standard deviation; s = 5.5
Sample size; n = 50
Confidence interval = 99%
Since sample size > 30, we will use the formula;
CI = x' ± zs/√n
Where;
x' is sample mean
s is sample standard deviation
n is sample size
z is z-value of the confidence interval
From the table attached, z for 99% = 2.3263
Thus;
CI = 22 ± (2.3263 × 5.5)/√50
CI = 22 ± 1.809
CI = 23.809 or 20.191
Lower confidence limit = 20.191
The piece-wise linear functions can be written as follows:
.
.
<h3>What is a linear function?</h3>
A linear function is modeled by:
y = mx + b
In which:
- m is the slope, which is the rate of change, that is, by how much y changes when x changes by 1.
- b is the y-intercept, which is the value of y when x = 0, and can also be interpreted as the initial value of the function.
For x less than 5, the y-intercept is of b = 3 and the function also gos through (2,2), hence the slope is:
m = (2 - 3)/(2 - 0) = -0.5.
Hence the rule is:
.
When x = 5, the function is constant at -5, hence:

For x less than 5, the function goes through points (6,3) and (7,2), hence the slope is:
m = (2 - 3)/(7 - 6) = -1.
Then:
y = -x + b
When x = 6, y = 3, hence the y-intercept is given as follows:
3 = -6 + b
b = 9.
Hence the rule is:
.
More can be learned about linear functions at brainly.com/question/25537936
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