Answer:
Step-by-step explanation:
<u>Confidence Interval</u>
When the population standard deviation 
is known, the formula for a confidence interval for a population mean 
is:
Where n is the sample size and z is the corresponding z-value from the standard normal distribution for the selected confidence level. The value of z for a 95% confidence interval is z=1.96. The rest of the values are
Calculating the confidence interval
Or, equivalently
Since the formula for the area of a circle is Pi x r squared, the area would be 81 x Pi (you teacher may want you to use Pi as 3.14 or put it in your calculator).
Answer:
To add or subtract functions, just add or subtract the values at each point where it makes sense. If the functions are given by formulas, you can just add or subtract the formulas (it doesn't matter whether you plug in values before or after).
Step-by-step explanation:
Answer:
A. 31/100
Step-by-step explanation:
Change 3/10 to hundreds:
3/10 × 10/10 = 30/100
The denominator (the bottom number) must be 100.
61 - 30 is 31.
The missing number is 31/100. See image.
