Answer:
=x3−13x2
Step-by-step explanation:
Kevin’s unit rate is $8.50/hr
Answer:
One solution (0, 3).
Step-by-step explanation:
As both expressions in x are equal to y:
3x + 3 = -2x + 3
3x + 2x = 3 - 3
5x = 0
x =0.
So y = 3(0) + 3 = 3.
Answer:
A sample of 179 is needed.
Step-by-step explanation:
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
.
That is z with a pvalue of
, so Z = 1.44.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
A previous study found that for an average family the variance is 1.69 gallon?
This means that 
If they are using a 85% level of confidence, how large of a sample is required to estimate the mean usage of water?
A sample of n is needed, and n is found for M = 0.14. So






Rounding up
A sample of 179 is needed.
Answer:
I hope I'm right in my answer to that