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.
When y=2 and y=5
1. 2y-1 and (3y-5+y or 4y-5)
when y=2 ; 2(2)-1 = 3 and 4(2)-5=3
when y=5 ; 2(5)-1 = 9 and 4(5)-5=15
----nonequivalent-----
2.5y+4 and (7y+4-2y or 5y+4)
so you don't have to place any value in because 5y+4 and 7y+4-2y are equal,
whatever you place any value in, it will be all the same then
-----equivalent------
and no need to find more
Answer: C. 113.1 cubic centimeters
Step-by-step explanation:
Volume of a sphere= 
(3.14)(r)^3
Since we know r then just plug in to get 4/3(3.14)(3)^3= 113.1
So the answer is C
Answer:
Step-by-step explanation:
So I'm assuming when you typed "log yhat=.4785 + 1.468x", you meant to write: 
. And generally a logarithm can be written in the form 
which can then be rewritten as 
, but since the log has no base, it's assumed to be 10. So in this case you have the equation:
, which can then be written in exponential form as:
Answer:
Gabe needs 20 liters of the 40% solution.
He also needs 40 liters of the 70% solution.
Step-by-step explanation:
Equation:
acid + acid = acid
0.40x + 0.70(60-x) = 0.60*60
40x + 70*60 - 70x = 60*60
-30x = -10*60
x = 20 liters
Gabe needs 20 liters of the 40% solution.
He also needs 40 liters of the 70% solution.
