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.
9514 1404 393
Answer:
A
Step-by-step explanation:
You can use x=0 and x=1 to find points that must be on the graph.
f(0) = 16·0.5^0 = 16
f(1) = 16·0.5^1 = 8
Only graph A matches these points.
Answer:
opposites
Step-by-step explanation:
1/2 : 1
2 : 4
3 : 6
Notice that every ratio consists of a number and double the number.
For 1/2 cup lemon juice, use 1 cup sugar.
The amount of sugar is twice the amount of lemon juice.
The ratio is 1:2
Since you are told the ratio is 1:r, that means r is 2.
The unit rate is 2 cups sugar per cup of lemon juice.
Answer:
Since he earned one third as many as Jose
it's 8
Step-by-step explanation: