Answer:
Step-by-step explanation:
Hello!
To study the threshold of hering the researcher took a random sample of 80 male college freshmen.
The students underwent an audiometry test where a tome was played and they had to press a button when they detected it. The researcher recorded the lowest stimulus level at which the tone was detected obtaining a sample mean of X[bar]= 22.2 dB and a standard deviation of S= 2.1 dB
To estimate the population mean, since we don't have information about the variable distribution but the sample size is greater than 30, you can use the approximation of the standard normal distribution:
X[bar] ± 
Where the semiamplitude or margin of error of the interval is:
d=
Using a 95% level 
d= 1.965 * 
d= 0.46
The point estimate of the population mean of the threshold of hearing for male college freshmen is X[bar]= 22.2 db
And the estimation using a 95%CI is [21.74;22.66]
I hope this helps!
Question 13-18 & 22-27 will all be answered the same way, so i will walk you through question 13: (6,4) y=3x-2
(x,y)=(6,4)
now that we know the first number in the parenthesis is the x value and the second number in the parenthesis is the y value we can plug it into the equation. (x=6,y=4)
4=3x-2 (add two to each side)
4+2=3x
6=3x (divide 3 from each side)
x=2
---------------
y=3(6)-2
y=18-2
y=16
-------------------
answer: (2,16)
now apply the same principles to the other problems!!! hope this helped!!!
Answer:
1.5
Step-by-step explanation:
Attached to this answer is the diagram of the box plot described in the question, and the means from the plot are calculated thus;
Students; no. of siblings
student 0 2
student 1 4
student 2 7
student 3 5
student 4 2
Total 20
Mean no. of siblings = (total number of siblings) ÷ (total number of students)
Note that number of students here are the once that had at least one sibling, others without siblings are not used in the calculation, hence 5 students (student-0 to student-4) make up total number of students, while the remaining 4 students (student-4 to student-9) are disregarded.
Therefore, mean = 20 ÷ 5 = 4 siblings.
Answer/Step-by-step explanation:
Ok so there is
3, 0-4 4, 5-9 2, 10-14 1, 15-19 1, 20-24
so you can get rid of the last one saying it has more than 1 number between 20-24.
The 3rd one has to short of numbers for 0-4.
the second one has way to many 0-4's when there should be 3 of them.
therefore your answer is The firstone.
-2.6 I think is the correct answer
