Answer:
The 90% confidence interval for the average monthly residential water usage for all households in this city is between 4401.3 gallons and 4598.7 gallons.
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 .
So it is z with a pvalue of , so
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.
The lower end of the interval is the sample mean subtracted by M. So it is 4500 - 98.7 = 4401.3 gallons
The upper end of the interval is the sample mean added to M. So it is 4500 + 98.7 = 4598.7 gallons
The 90% confidence interval for the average monthly residential water usage for all households in this city is between 4401.3 gallons and 4598.7 gallons.
Answer:
Combination without repetition
Step-by-step explanation:
The fruit he chooses doesn’t matter because he’s simply throwing them in his lunch box (so it’s a combination). And because there is a limited amount of fruit it is without repetition.
Answer:
60 baseball and 20 football
Step-by-step explanation:
D
Because to cancel out division you use multiplication
Answer:
8
Step-by-step explanation:
When you subtract the 9-1=8