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:
It's no correlation
Step-by-step explanation:
It's no correlation because the dots are scattered everywhere. There's no exact direction they all lead to.
The best thing to do is to rewrite the fractions as decimals
-2/3 is approx. equal to -0.6666667
So a little past half way (to the left) between -1 and 0
1 1/5 is 1.5 so that is right between 1 and 2
Hope this helps :)
Answer:
15 scores are less than 90
Step-by-step explanation:
Total 11 scores are less than 90 not 15
Answer:
6
Step-by-step explanation:
