Answer:
Interval [16.34 , 21.43]
Step-by-step explanation:
First step. <u>Calculate the mean</u>

Second step. <u>Calculate the standard deviation</u>



As the number of data is less than 30, we must use the t-table to find the interval of confidence.
We have 6 observations, our level of confidence DF is then 6-1=5 and we want our area A to be 80% (0.08).
We must then choose t = 1.476 (see attachment)
Now, we use the formula that gives us the end points of the required interval

where n is the number of observations.
The extremes of the interval are then, rounded to the nearest hundreth, 16.34 and 21.43
Answer: 1957
Step-by-step explanation:
What problem i dont see nun
(f+g)(3)=f(3)+g(3)
f(x)=7 so f(3)=7
g(x)=x+5 so g(3)=3+5=8
(f+g)(3)=f(3)+g(3)=7+8=15
Option B is correct
Why
3x=21
3(7) =21
21=21
Step-by-step explanation: