Answer:
The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the z-score that has a p-value of
.
427 had paid for coaching courses and the remaining 2733 had not.
This means that 
95% confidence level
So
, z is the value of Z that has a p-value of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).
Answer:
$12,087,912.1
Step-by-step explanation:
is in scientific notation, to get this into normal number, we take the decimal point and move it "9" times to the right [whatever power of 10 we have, we move to right (if positive).] Then we fillup the rest with zeros.
So we have:

This is the revenue.
We do similar process for time:

This is the time , in minutes.
We want revenue PER minute, that means we divide the total revenue by total time, that would be:

The revenue earned per minute is $12,087,912.1
To find this out we have to add 5 tens and 13 ones.
5 tens is equal to
10 + 10 + 10 + 10 + 10 = 50
And 13 ones is equal to
1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 13
Now add 50 and 13
50 + 13 = 63
So your answer is 63
good Luck! :)
1:
Length: 7
Width:2
Perimeter: 18
2:
Length: 5
Width: 2.8
Perimeter: 15.6
Answer:
Orange = 12
Grape = 15
Cola = 23
Step-by-step explanation:
Turning this into equations you can give each soda a variable
Cola = C | Grape = G | Orange = R
Then you get:
8 + G = C
R + 3 = G
C + G + R = 50
We want to get a variable all by itself in an equation so first I'm going to put the second equation (R + 3 = G) in the first (8 + G = C) by replacing the G to get
8 + (R + 3) = C Combine the variables 11 + R = C and put that new equation into the last equation
(11 + R) + G + R = 50
Now plug our original second equation (R + 3 = G) into our third to get
(11 + R) + (R + 3) + R = 50
Combine and get
14 + 3R = 50 Subtract over the 14
3R = 36 Divide by 3
Orange Sodas = 12
Our new 3rd Equation is now: C + G + 12 = 50, subtract over 12 to get
C + G = 38
Plug either equation 1 or 2 into that one, I'll do 1
(8 + G) + G = 38
8 + 2G = 38
2G = 30
Grape Sodas = 15
Now our 3rd equation is C + 15 = 38, subtract over 15
Cola Sodas = 23
Orange = 12
Grape = 15
Cola = 23
12 + 15 + 23 = 50