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:
Step-by-step explanation:
5/8 +1/n = 7/8
1/n= -5/8 +7/8
1/n = 2/8
1/n= 1/2
then you would try to get n by itself
by dividing n/1 to 1/n and 1/2
12k-1 is the simplified answer
First, let's simplify the inequality as much as we can:
-4x + 7 > 15
-4x > 8
Divide by -4:
x < -2
Answer:
Step-by-step explanation:
since it starts at 62 and finishes at 150 u can find out that the increase in temp is 150F and since it increases by 8 every minute u can come to find that the increase in temp (150) divided by the amount it increases 8 is 18.75 which is the amount of minutes it took