Answer:
The 99% confidence interval for the population mean reduction in anxiety was (1.2, 8.6).
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used 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 = 27 - 1 = 26
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 26 degrees of freedom(y-axis) and a confidence level of
. So we have T = 2.7787.
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 4.9 - 3.7 = 1.2.
The upper end of the interval is the sample mean added to M. So it is 4.9 + 3.7 = 8.6.
The 99% confidence interval for the population mean reduction in anxiety was (1.2, 8.6).
Subtract the 7 from both sides,
you are left with
11=y
Answer:
45, 36
Step-by-step explanation:
let x y minutes be the time for pipes to fill the tank, let n be the water needed to fill the tank.
x-y=9
(n/x)*20+(n/y)*20=n
n is removed by dividing the 2nd equation by n
here u get:
(1/x+1/y)*20=1
you sub x=9+y into the above equation
1/y+1/(9+y)=1/20
((9+y)+(y))*20=(9+y)(y)
180+40y=9y+y2
y2-31y-180=0
then use the quadratic formula and u will find y=36 or -5
-5 is rejected because it is negative
x=36+9=45
therefore it is 36 mins and 45 mins
The answer is F(x) = 900x + 600
Let x stands for the number of months
The apartment is rented for $900 a month, so every month it will be paid 900x (for example, for one month (x = 1), you will pay 900 · 1 = $900, for three months (x = 5), you will pay 900 · 5 = $4500, etc.)
A security deposit is paid only once and is not dependent on the number of months. So, its value is only 600.
These two values must be summed up because both must be paid, nothing is to subtract. Therefore, the function f(x) for apartments that rent for $900 a month and a security deposit of $600 is:
f(x) = 900x + 600