Answer:
Critical value: T = 1.337
The 80% confidence interval for the mean repair cost for the stereos is between $45.991 and $86.689
Step-by-step explanation:
We have the standard deviation for the sample. So we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 17 - 1 = 16
80% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 16 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.337, which is the critical value
The margin of error is:
M = T*s = 1.337*15.22 = 20.349
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 66.34 - 20.349 = $45.991
The upper end of the interval is the sample mean added to M. So it is 66.34 + 20.349 = $86.689
The 80% confidence interval for the mean repair cost for the stereos is between $45.991 and $86.689
Answer:
Question 13: For age groups y=1 and y=1.3 response is 8 microseconds.
Question 14: The club was making a loss between 11.28 and 4.88 years.
Step-by-step explanation:
Question 13:
The age group y for which the response rate R is 8 microseconds is given by the solution of the equation

We graph this equation and find the solutions to be

Since only positive solutions for y are valid in the real world we take only those.
Thus only for age groups y=1 and y=1.3 the response is 8 microseconds.
Question 14:
The footbal club is making a loss when 
Or

We graph this inequality and find the solutions to be
and 
Since in the real world only positive values for t are valid, we take the the second solution to be true.
Thus the club was making a loss in years 
Answer:
The correct explaination is Point G can be the centroid because 12:6 equals 2:1
Step-by-step explanation:
Given in triangle ABC, the segments drawn from vertices intersect at point G.
Segment FG measures 6 cm and and segment FC measures 18 cm.
FG = 6 cm & FC = 18 cm
and also FC = FG + GC
18 = 6 + GC ⇒ GC = 12
Note: The centroid divides each median in a ratio of 2:1
& 12:6 give rise to 2:1
Hence, the correct explaination for this is Point G can be the centroid because 12:6 equals 2:1
Answer:
f(x) = 500(2)^x
Step-by-step explanation:
Let's assume the initial x value is 0
500(0)^2 = 0
100(0)^5 = 0
500(2)^0 = 500
500(0)^2 = 0
Answer: The percent of change is 25%
Step-by-step explanation:
$525 - $393.75 = $131.25
131.25 (amount of change)/525 ( original amount) x 100
= 25%