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:
true
Step-by-step explanation:
If you have to show your work...
8.2 x 9.5
8.2
x 9.5
-----------
410
+ 7380
-----------
7,790 miles
hoped this helped.
Answer:
The answer would be 150,000 to 249,999
Answer:
8.24 grams/marble
Step-by-step explanation:
Average mass = (total mass)/(number of marbles)
Here, that would be:
824 g
------------------- = 8.24 grams/marble
100 marbles