-3/4
Step-by-step explanation:
f(x) = (1,2) & (-3,5)
f(x) = y²-(y¹)
_____
x²-(x¹)
y=5-2
___
-3-1
y=-3/4
First you find the median which is 4. The mean is calculated by the sum of the distribution divided by the amount of numbers in the distribution (20). The mean comes out to be 4.35. Subtract 4.35 from 4 and your answer is .35.
Answer:
The sample mean is
b.3.55
The margin of error is
0.32
Step-by-step explanation:
Deep explanation about a confidence interval
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the mean subtracted by M. So it is 6.4 - 0.3944 = 6.01 hours.
The upper end of the interval is the mean added to M. So it is 6.4 + 0.3944 = 6.74 hours.
In this problem:
The deep explanation is not that important.
We just have to recognize that the interval has a lower end and an upper end. The distance from both the upper and the lower end to the mean is M. This means that the sample mean is the halfway point between the lower end and the upper end.
The margin of error is the distance of these two points(lower and upper end) to the mean.
In our interval
Lower end: 3.23
Upper end: 3.87
Sample mean

So the correct answer is:
b.3.55
The margin of error is
3.87 - 3.55 = 3.55 - 3.23 = 0.32
Using proportions, it is found that the Customer Acquisition Cost was of $1,215.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount.
In this problem, the customer acquisition cost is the spending in sales divided by the number of customers added.
80 customers were added, considering costs of 1200 + 9000 + 87000 = $97,200, hence:
97200/80 = $1,215.
More can be learned about proportions at brainly.com/question/24372153
Step-by-step explanation:
so the ratio of the recipe is 32/48 of pineapple juice and orange juice.
that can be simplified to the ratio of 2/3.
now, she has only 20 floz of pineapple juice.
20/x = 2/3
60/x = 2
60 = 2x
x = 60/2 = 30
she needs 30 floz of orange juice with the 20 floz of pineapple juice to maintain the prescribed ratio for fruit punch.